SELECTIVE INSURANCE GROUP INC (SIGI)

ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

Forward-Looking Statements

The terms “Company,” “we,” “us,” and “our” refer to Selective Insurance Group, Inc. (the “Parent”) and its subsidiaries, except as expressly indicated or the context otherwise requires. Certain statements in this Quarterly Report on Form 10‑Q, including information incorporated by reference, are “forward‑looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995 (“PSLRA”). The PSLRA provides a safe harbor for forward‑looking statements under the Securities Act of 1933 and the Securities Exchange Act of 1934.

Forward‑looking statements include our expectations, intentions, beliefs, projections, estimates, or forecasts regarding future events or financial performance. These statements involve known and unknown risks, uncertainties, and other factors that may cause our actual results, activity levels, or performance to differ materially from those expressed or implied in the forward‑looking statements. In some cases, forward‑looking statements may be identified by words such as “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “believe,” “intend,” “estimate,” “project,” “predict,” “potential,” “pro forma,” “seek,” “target,” “continue,” or similar terms.

Forward‑looking statements are predictions only, and we cannot guarantee that the expectations expressed in such statements will prove correct. We undertake no obligation to publicly update or revise any forward‑looking statements, except as required by law.

We discuss factors that could cause actual results to differ materially from those expressed in forward‑looking statements in Item 1A, “Risk Factors,” of this Form 10‑Q. These risk factors may not be exhaustive. We operate in a continually changing business environment, and new risk factors may emerge at any time. We cannot predict these new factors, their potential impact on our business, or the extent to which any factor – or combination of factors – may cause actual results to differ materially from those expressed in forward‑looking statements. In light of these risks, uncertainties, and assumptions, the forward‑looking events discussed in this report may not occur.

Introduction

We classify our business into four reportable segments:

•Standard Commercial Lines;

•Standard Personal Lines;

•Excess and Surplus Lines ("E&S Lines"); and

•Investments.

For additional information about these segments, refer to Note 9. "Segment Information" in Item 1. "Financial Statements." of this Form 10-Q and Note 12. "Segment Information" in Item 8. "Financial Statements and Supplementary Data." of our Annual Report on Form 10-K for the year ended December 31, 2025 ("2025 Annual Report").

We write our Standard Commercial and Standard Personal Lines products and services through nine of our insurance subsidiaries, some of which participate in the federal government's National Flood Insurance Program's ("NFIP") Write Your Own Program. We write our E&S products through another subsidiary, Mesa Underwriters Specialty Insurance Company, a nationally authorized non-admitted carrier for customers who generally cannot obtain coverage in the standard marketplace. Collectively, we refer to our ten insurance subsidiaries as the "Insurance Subsidiaries."

The following is Management’s Discussion and Analysis ("MD&A") of our financial condition and consolidated results of operations, including an evaluation of the amounts and certainty of cash flows from operations and outside sources, trends, and uncertainties that may have a material impact in future periods. Investors should read the MD&A in conjunction with Item 1. "Financial Statements." of this Form 10-Q and the consolidated financial statements in our 2025 Annual Report filed with the United States ("U.S.") Securities and Exchange Commission.

In the MD&A, we discuss and analyze the following:

•Critical Accounting Policies and Estimates;

•Financial Highlights of Results for the second quarters ended June 30, 2026 ("Second Quarter 2026") and June 30, 2025 ("Second Quarter 2025"); and the six-month periods ended June 30, 2026 ("Six Months 2026") and June 30, 2025 ("Six Months 2025")

•Results of Operations and Related Information by Segment;

•Federal Income Taxes;

•Liquidity and Capital Resources; and

•Ratings.

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Critical Accounting Policies and Estimates

Our unaudited interim consolidated financial statements include amounts for which we have made informed estimates and judgments for transactions not yet completed. These estimates and judgments affect the reported amounts in our consolidated financial statements. Our 2025 Annual Report outlines the estimates and judgments most critical to the preparation of the consolidated financial statements: (i) reserve for loss and loss expense; (ii) investment valuation and the allowance for credit losses on available-for-sale ("AFS") fixed income securities; and (iii) reinsurance. These estimates and judgments require our use of assumptions about highly uncertain matters that could change as facts and circumstances develop. Different estimates or judgments could result in materially different reported amounts. For additional information regarding our critical accounting policies and estimates, refer to pages 38 through 45 of our 2025 Annual Report.

Financial Highlights of Results for Second Quarter and Six Months 2026 and Second Quarter and Six Months 20251

1Refer to the Glossary of Terms attached to our 2025 Annual Report as Exhibit 99.1 for definitions of terms used in this Form 10-Q.

2Non-GAAP operating income (loss), non-GAAP operating income (loss) per diluted common share, and non-GAAP operating ROE are comparable to net income (loss) available to common stockholders, net income (loss) available to common stockholders per diluted common share, and ROE, respectively, but exclude after-tax net realized and unrealized gains and losses on investments included in net income (loss). Adjusted book value per common share is comparable to book value per common share, but excludes total after-tax unrealized gains and losses on investments included in accumulated other comprehensive income (loss). These non-GAAP measures are important financial measures used by us, analysts, and investors because the timing of realized and unrealized investment gains and losses on securities in any given period is largely discretionary. In addition, net realized and unrealized investment gains and losses on investments could distort the analysis of trends.

The tables below provide reconciliations of our GAAP to non-GAAP measures:

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[[GREPCENT_TABLE]]
[["Reconciliation of book value per common share to adjusted book value per common share","","Quarter ended June 30,","","Six Months ended June 30,"],["","2026","","2025","","2026","","2025"],["Book value per common share","","$","58.13","","","52.09","","","$","58.13","","","52.09"],["Total unrealized investment (gains) losses included in accumulated other comprehensive income (loss), before tax","","

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Forward-Looking Statements

The terms "Company," "we," "us," and "our" refer to Selective Insurance Group, Inc. (the "Parent") and its subsidiaries, except as expressly indicated or the context otherwise requires. Certain statements in this Annual Report on Form 10-K, including information incorporated by reference, are “forward-looking statements” defined in the Private Securities Litigation Reform Act of 1995 ("PSLRA"). The PSLRA provides a forward-looking statement safe harbor under the Securities Act of 1933 and the Securities Exchange Act of 1934. These statements discuss our intentions, beliefs, projections, estimations, or forecasts of future events and financial performance. They involve known and unknown risks, uncertainties, and other factors that may cause our or our industry's actual results, activity levels, or performance to materially differ from those in or implied by the forward-looking statements. In some cases, forward-looking statements include the words "may," "will," "could," "would," "should," "expect," "plan," "anticipate," "attribute," "confident," "strong," "target," "project," "intend," "believe," "estimate," "predict," "potential," "pro forma," "seek," "likely," "continue," or comparable terms. Our forward-looking statements are only predictions; we cannot guarantee or assure that such expectations will prove correct. We undertake no obligation to publicly update or revise any forward-looking statements for any reason except as required by law.

We discuss the factors that could cause our actual results to differ materially from our projections, forecasts, or estimates in forward-looking statements in Item 1A. "Risk Factors." of this Form 10-K. These risk factors may not be exhaustive. We operate in a constantly changing business environment, and new risk factors may emerge at any time. We cannot predict these new risk factors, their impact on our businesses, or the extent to which one or any combination of factors may cause actual results to differ materially from any forward-looking statements. Given these risks, uncertainties, and assumptions, the forward-looking events we discuss might not occur.

Introduction

We classify our business into four reportable segments:

•Standard Commercial Lines;

•Standard Personal Lines;

•Excess and Surplus Lines ("E&S Lines"); and

•Investments.

For more details about these segments, refer to Note 1. "Organization" and Note 12. "Segment Information" in Item 8. "Financial Statements and Supplementary Data." of this Form 10-K.

We write our Standard Commercial and Standard Personal Lines products and services through nine of our insurance subsidiaries, some of which participate in the federal government's National Flood Insurance Program's ("NFIP") Write Your Own Program ("WYO"). We write our E&S products through another subsidiary, Mesa Underwriters Specialty Insurance

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Company ("MUSIC"), a nationally-authorized non-admitted platform for customers who generally cannot obtain coverage in the standard marketplace. Collectively, we refer to our ten insurance subsidiaries as the "Insurance Subsidiaries."

The following is Management's Discussion and Analysis ("MD&A") of our financial condition and consolidated results of operations, including an evaluation of the amounts and certainty of cash flows from operations and outside sources, trends, and uncertainties that may have a material impact in future periods. The MD&A discusses and analyzes our 2025 results compared to 2024. Investors should read the MD&A in conjunction with Item 8. "Financial Statements and Supplementary Data." of this Form 10-K. For discussion and analysis of our 2024 results compared to 2023, refer to Item 7. "Management’s Discussion and Analysis of Financial Condition and Results of Operations." of our Annual Report on Form 10-K for the fiscal year ended December 31, 2024.

In the MD&A, we will discuss and analyze the following:

•Critical Accounting Policies and Estimates;

•Financial Highlights of Results for Years Ended December 31, 2025, 2024, and 2023;

•Results of Operations and Related Information by Segment;

•Federal Income Taxes; and

•Liquidity and Capital Resources.

Critical Accounting Policies and Estimates

We have identified the policies and estimates critical to our business operations and understanding of our results of operations. We consider the policies and estimates most critical to the preparation of the Financial Statements to be (i) reserve for loss and loss expense, (ii) investment valuation and the allowance for credit losses on available-for-sale ("AFS") fixed income securities, and (iii) reinsurance.

Reserve for Loss and Loss Expense

Significant time can elapse between the occurrence of an insured loss, the reporting of a claim to us, and the final claim settlement and payment. Insurers establish reserves as balance sheet liabilities to recognize liabilities for unpaid loss and loss expenses. The following tables provide case and incurred but not reported ("IBNR") reserves for loss and loss expenses and reinsurance recoverable on unpaid loss and loss expense as of December 31, 2025 and 2024:

1Includes our flood loss exposure related to our participation in the NFIP's WYO program, to which we cede 100% of our WYO flood losses.

2Includes general liability (97% of net reserves) and commercial auto liability coverages 3% of net reserves).

3Includes commercial property (94% of net reserves) and commercial auto property coverages 6% of net reserves).

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1Includes our flood loss exposure relates to our participation in the NFIP's WYO program, to which we cede 100% of our flood losses.

2Includes general liability (97% of net reserves) and commercial auto liability coverages (3% of net reserves).

3Includes commercial property (93% of net reserves) and commercial auto property coverages (7% of net reserves).

The Insurance Subsidiaries' net loss and loss expense reserves duration was approximately 3.0 years at both December 31, 2025 and December 31, 2024.

How the reserve is established

Reserve for loss and loss expense includes case reserves on reported claims and IBNR reserves.  Case reserves are estimated for each individual claim based on facts and circumstances known at the time.  Case reserves may be adjusted up or down as the claim's specific facts and circumstances change. IBNR reserves are established at more aggregated levels and include provisions for (i) claims not yet reported, (ii) future development on reported claims, (iii) closed claims that could reopen in the future, and (iv) anticipated salvage and subrogation recoveries.

We conduct quarterly internal reserve reviews using our own loss experience, considering various internal and external factors. Changes in claim dynamics can inherently alter paid and reported development patterns. Although our reserve analysis selections aim to account for these impacts, estimated reserves involve greater risk of variability.

In addition to our internal reserve reviews, an external consulting actuary performs an independent semiannual reserve review. We do not rely on the external consulting actuary's report to determine our recorded reserves, but we review and discuss our observations on trends, key assumptions, and actuarial methodologies with our consulting actuary. Our independent consulting actuary issues the annual statutory Statements of Actuarial Opinion for our Insurance Subsidiaries.

For additional information on our accounting policy for reserve for loss and loss expense, refer to Note. 2. "Summary of Significant Accounting Policies" in Item 8. "Financial Statements and Supplementary Data." of this Form 10-K.

Range of Reasonable Reserve Estimates

We have estimated a range of reasonable reserve estimates for net loss and loss expense of $5,694 million to $6,960 million at December 31, 2025. This range reflects low and high reasonable reserve estimates determined after using judgment to adjust the methods, factors, and assumptions selected within the internal reserve review. This approach produces a range of reasonable reserve estimates but does not represent a distribution of all possible outcomes. Consequently, final outcomes may be greater or less than the estimates.

The range of reasonable reserve estimates increased as of December 31, 2025, relative to December 31, 2024. This increase was primarily related to reserve growth commensurate with our net premiums earned ("NPE") growth.

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Changes in Reserve Estimates (Loss Development)

Our quarterly reserving process may lead to changes in the recorded reserves for prior accident years, referred to as favorable or unfavorable prior year loss and loss expense development. In 2025, we experienced net unfavorable prior year loss development of $77.5 million, compared to net unfavorable development of $285.3 million in 2024 and net unfavorable development of $10.0 million in 2023. The following table summarizes prior year development by line of business:

A detailed discussion of recent reserve development by line of business follows.

Standard Market General Liability Line of Business

At December 31, 2025, our general liability line of business had recorded reserves, net of reinsurance, of $2.9 billion, representing 46% of our total net reserves. In 2025, this line experienced unfavorable reserve development of $40.0 million, primarily due to the impact of social inflation that increased loss severities in accident years 2022 and 2023. We attribute the increased severities to elevated social inflation, which we view as an industry dynamic characterized by higher claimant propensity for attorney representation and litigation, longer settlement times, and higher settlement values. Similarly, this line experienced unfavorable development in 2024 of $316.0 million, attributable to the impact of social inflation driving increased loss severities in accident years 2020 through 2023.

The general liability line of business presents a diverse set of exposures. Various factors influence losses and loss trends, including legislative enactments, judicial decisions, and economic and social inflation. Economic inflation directly impacts our claims severities by increasing the costs of raw materials, medical procedures, and labor. Social inflation may impact both claim frequency and severity by affecting (i) claimant propensity to file a claim, (ii) the percentage of claimants who engage lawyers, and (iii) broader liability interpretations and the nature and amounts of judicial verdicts and associated awards, all influencing future settlement values. We monitor claim litigation rates regularly. We have observed the percentage of general liability claims with plaintiff attorney involvement increasing in recent periods. Other social inflationary factors, including the increased prevalence of third-party litigation funding, claimants' willingness to undergo surgery, evolving plaintiff attorney strategies and tactics, and broadening liability definitions and interpretations, are also impacting claims severities.

We have exposure to abuse or molestation claims, mainly through policies that we (i) underwrite through our Community and Public Services ("CAPS") strategic business unit and (ii) issue to schools, religious institutions, child-care facilities, and other social services. These CAPS business unit customers represented approximately 10% of our total Standard Commercial Lines net premiums written ("NPW") in 2025 and 2024. We continue to actively manage policy limits and monitor each jurisdiction's statute of limitations to ensure our rate level reflects increased exposure wherever regulations allow. We also engage our risk management specialists, many of whom are Certified Praesidium Guardians, to understand our insureds' screening, training, and monitoring policies and collaborate with them to improve their risk prevention in these areas. These underwriting and pricing actions have positioned the portfolio for future profitability but limited our CAPS growth in recent years.

Certain states have enacted state laws that extend the statute of limitations or permit windows for abuse or molestation claims and lawsuits that statutes of limitations previously barred. Consequently, we have received claims decades after the alleged acts involving complex claims coverage determinations, potential litigation, higher defense costs, and the need to collect from reinsurers under older reinsurance agreements. Our claims and actuarial departments actively monitor these claims to identify changes in frequency or severity and any emerging or shifting trends.

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Our active monitoring of claim patterns and emerging or shifting trends helps us better understand this rapidly evolving exposure. However, the ultimate impact of social, political, and legal trends remains highly uncertain and could substantially impact the ultimate settlement values for these claims.

In addition, we have continued to implement underwriting changes in this line of business that we believe will lead to improved profitability. These changes may impact portfolio composition and may affect paid and reported development patterns. While our reserve analyses incorporate methods that adjust for these changes, our estimated reserves have a greater risk of fluctuation.

Standard Market Commercial Automobile Line of Business

At December 31, 2025, our commercial automobile line of business had recorded reserves, net of reinsurance, of $1.3 billion, representing 21% of our total net reserves. In 2025, this line experienced unfavorable prior year reserve development of $120.4 million, driven by increased severities for accident years 2022 through 2024, with 2024 being the primary driver. In 2024, this line experienced unfavorable prior year reserve development of $19.5 million, driven by increased loss expenses in accident year 2023.

The commercial automobile line has experienced unfavorable trends in recent years that have negatively affected the industry's results and ours. These unfavorable trends are a result of risky driving behaviors, such as speeding, distracted driving, and driving under the influence, which have reduced in frequency but resulted in significant severity increases. Risky driving behaviors and the impacts of social inflation continue to pressure this line's claim severities. As of year-end 2025, frequencies remained somewhat below pre-pandemic levels due to changes in commuting patterns.

Over the last several years, we have implemented underwriting changes in this line of business that we believe will lead to improved profitability. These changes may impact portfolio composition and may affect paid and reported development patterns. While our reserve analyses incorporate methods that adjust for these changes, our estimated reserves have a greater risk of fluctuation.

Standard Market Workers Compensation Line of Business

At December 31, 2025, our workers compensation line of business had recorded reserves, net of reinsurance, of $741 million, representing 12% of our total net reserves. During 2025, this line experienced favorable reserve development of $90.0 million, primarily due to improved loss severities in accident years 2022 and prior. Similarly, this line experienced favorable reserve development during 2024 of $45.0 million, primarily due to improved loss severities in accident years 2022 and prior. During both 2025 and 2024, the lower-than-expected loss emergence was partly due to (i) lower than initially anticipated medical inflation and (ii) our various implemented claims initiatives. Because injured workers can receive related medical treatment for an extended time, decreases in medical inflation can cause favorable loss development over an extended number of accident years.

A variety of issues can impact the workers compensation line of business, including:

•Unexpected changes in medical cost inflation – The industry has experienced an extended period of lower medical claim cost inflation. Changes to our historical workers compensation medical costs and potential changes in future medical inflation could increase reserve variability;

•Changes in statutory workers compensation benefits – Statutory benefit changes may affect all outstanding claims, including past and not-yet-settled claims. Depending on the social and political climate, these changes may either increase or decrease associated claim costs; and

•Changes in utilization of the workers compensation system – These changes may be driven by economic, legislative, or other changes, like increased use of prescriptions for pharmaceuticals, more complex medical procedures, changes in permanently injured workers' life expectancy, and health insurance availability. Industry analysis has indicated recent increases in workers compensation system utilization.

Standard Market Personal Automobile Line of Business

At December 31, 2025, our personal automobile line of business had recorded reserves, net of reinsurance, of $177 million, representing 3% of our total net reserves. This line experienced unfavorable prior year reserve development of $13.0 million in 2025, primarily due to increased loss severities in accident year 2024 concentrated in New Jersey. This line experienced unfavorable prior year reserve development of $11.1 million in 2024, primarily due to increased loss severities in accident years 2022 through 2023.

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We view increased vehicle repair cost trends as the likely causes of rising severities, exacerbated by riskier driving behaviors, including distracted driving. We continuously recalibrate our predictive models and refining our underwriting and pricing approaches. This includes prioritizing additional rate filings by state and further refining our pricing factors.

The rate increases we filed began to take effect early in 2023, and their volume and magnitude increased throughout 2024, remaining strong in 2025, though slightly lower than 2024. We expect these rates to continue outpacing loss trends in 2026, but at lower levels than those seen in 2024 and 2025. While we believe these underwriting and pricing changes will ultimately lead to improved profitability and greater stability, they may also alter our exposure profile. This could impact the patterns of paid and reported claims development, leading to increased reserve uncertainty in the near term.

E&S Casualty Lines of Business

At December 31, 2025, our E&S casualty lines of business had recorded reserves, net of reinsurance, of $755 million, representing 12% of our total net reserves. In 2025, this line experienced unfavorable prior year reserve development of $10.0 million, primarily due to increased loss severities in accident years 2020 through 2023. In 2024, this line experienced unfavorable prior-year reserve development of $20.0 million, primarily due to increased loss severities in accident years 2023 and prior.

Some of the risk factors for the general liability line also affect the E&S casualty lines. These include (i) economic inflation, such as materials and labor costs and (ii) social inflationary trends, such as increased attorney involvement, broader liability findings, and more generous settlement awards. In response to these social inflationary trends, we have been embedding higher severity assumptions in our initial loss ratio estimates.

The E&S marketplace naturally leads to shifts in portfolio mix over time. These changes in business mix may affect paid and reported development patterns. Our reserve analyses incorporate methods that adjust for these changes, but our estimated reserves have a greater risk of fluctuation.

Other impacts that create additional loss and loss expense reserve uncertainty

Claims Initiative Impacts

Our Claims Department continually identifies areas for improvement and efficiency to increase our policyholder value proposition. These improvements may lead to changes in claims practice that affect average case reserve levels and claims settlement rates, which directly impact the data we use to project ultimate loss and loss expense. While these changes may increase uncertainty in our estimates in the short term, we expect refined claims process management to create longer-term benefits.

Our internal reserve analyses incorporate actuarial projection methods that make adjustments for changes in case reserve adequacy and claims settlement rates. These methods adjust our historical loss experience to the current case adequacy or settlement rate level, providing a more consistent basis for projecting future development patterns. Because these projection methods have their own assumptions and judgments, no single method can be considered definitive.

Unanticipated Changes in Economic Inflation

United States ("U.S.") fiscal and monetary policy and global economic conditions bring additional inflationary trend uncertainty. Changes in inflation affect the ultimate settlement costs for many of our lines of business, with the most significant reserve impact on the longer-tailed lines, such as general liability and workers compensation. Uncertainty about future inflation or deflation creates the potential for additional reserve variability in these lines of business.

Sensitivity analysis: Potential impact on reserve estimates due to changes in key assumptions

Our process to establish reserves includes a variety of key assumptions, such as:

•The selection of loss and loss expense development factors;

•The weight applied to each individual actuarial projection method;

•Projected future loss trends; and

•Expected claim frequencies, severities, and ultimate loss and loss expense ratios for the current accident year.

The importance of any single assumption depends on several considerations, such as line of business and accident year. If the actual experience emerges differently than the assumptions underlying the reserve process, possible changes in our reserve estimates could be material to the results of operations in future periods. We conduct sensitivity tests that highlight potential impacts to loss and loss expense reserves for the major casualty lines of business under different scenarios. These tests consider each assumption and line of business individually, without considering the correlation between lines of business and accident years. The results (i) do not constitute an actuarial range, (ii) show possible impacts from variations in certain key assumptions,

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and (iii) offer no assurance that future loss and loss expense emergence will be consistent with our current or alternative assumptions.

Changes in internal and external trends and operational changes may manifest as changes in loss and loss expense development patterns. These patterns are a key assumption in the reserving process, as are the current accident year expected loss and loss expense ratios. These ratios are developed through a rigorous process of projecting recent accident years' experience to an ultimate settlement basis. They are then adjusted to the current accident year's pricing and loss cost levels. The impact of changes to underwriting portfolio and claims handling practices is estimated and reflected where appropriate. Nonetheless, the ultimate loss and loss expense ratios may differ from current estimates.

The two tables below illustrate the sensitivities of loss and loss expense reserves to these key assumptions for the major casualty lines. The first table displays estimated impacts from changes in expected reported loss and loss expense development patterns for our major casualty lines of business. It shows line of business reserve impacts if the actual calendar year incurred amounts are greater or less than current expectations by the selected percentages. While judgmental, the selected percentages by line are based on the reserve range analysis and the actual historical reserve development for the line of business. The second table displays the estimated impacts of changes to the expected loss and loss expense ratios for the current accident year. It shows reserve impacts by line of business if the expected loss and loss expense ratios for the current accident year are greater or less than current expectations by the selected percentages.

There is some overlap between the impacts shown in the tables. For example, increases in the calendar year development would ultimately impact our view of the current accident year's loss and loss expense ratios. However, these tables provide perspective on the sensitivity of each key assumption. While the changes represent outcomes based on reasonably likely changes to our underlying reserving assumptions, they do not represent a range of possible outcomes and our reserves could increase or decrease significantly differently.

Asbestos and Environmental Reserves

Our general liability, businessowners' policies, and homeowners reserves include exposure to asbestos and environmental claims. The emergence of these claims occurs over an extended period and can be unpredictable. The total recorded net loss and loss expense reserves for these claims were $27.6 million as of December 31, 2025, and $27.4 million as of December 31, 2024, with asbestos claims constituting approximately 41% of these reserves in 2025 and 44% in 2024.

Environmental claims have arisen from Standard Commercial Lines policies issued to municipal governments and small non-manufacturing commercial customers for landfill exposures, and Standard Personal Lines homeowners policies related to leaking underground storage tanks. Asbestos claims have generally arisen from Standard Commercial Lines policies issued to (i) various distributors of asbestos-containing products, such as electrical and plumbing materials and (ii) contractors exposed to or handling asbestos-containing products, such as heating, ventilation, and air conditioning contractors. These claims are handled by a centralized and specialized asbestos and environmental claim unit that establishes case reserves based on each claim's then-known facts and circumstances, which IBNR reserves supplement.

Estimating IBNR reserves for asbestos and environmental claims is difficult because these claims have delayed and inconsistent reporting patterns. Significant uncertainties are associated with estimating critical reserve assumptions, such as average clean-

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up costs, third-party costs, potentially responsible party shares, allocation of damages, litigation and coverage costs, and potential state and federal legislative changes.

Other Latent Exposures

We have other latent and continuous trigger exposures in our ongoing portfolio. Examples include claims for construction defect and abuse or molestation, including in states that have increased and expanded the statute of limitations. We manage our exposure to these liabilities through our underwriting and claims practices, which include dedicated claim units, like we do for asbestos and environmental claims. The impact of social, political, and legal trends on these claims remains highly uncertain, so the development and adequacy of our related loss and loss expense reserves remain highly uncertain. Some of these exposures remain in our ongoing portfolio and are reserved in aggregate, with other exposures within the line of business reserves. We remove other unusual and highly uncertain exposures, like toxic product claims involving diacetyl, lead paint, and silica, from our traditional reserve analysis and undertake a separate review for them.

Investment Valuation and the Allowance for Credit Losses on AFS Fixed Income Securities

Investment Valuation

Accounting guidance defines the fair value of our investment portfolio as the exit price or amount that would be (i) received to sell an asset or (ii) paid to transfer a liability in an orderly transaction between market participants. When determining an exit price, we must rely on observable market data, if available. Most securities in our equity portfolio have readily determinable fair values and are recorded at fair value with changes in unrealized gains or losses recognized through income. Our AFS fixed income securities portfolio is recorded at fair value, and the related unrealized gains or losses are reflected in stockholders' equity, net of tax. For our AFS fixed income securities portfolios, fair value is a key factor in the measurement of (i) losses on securities for which we have the intent to sell and (ii) changes in the allowance for credit losses.

Approximately 88% of our investments measured at fair value are classified as either Level 1 or Level 2 in the fair value hierarchy and are priced using observable inputs for identical or similar assets. About 12% are classified as either (i) Level 3 and are based on unobservable market inputs because the related securities are not traded on a public market or (ii) not leveled because the related securities are measured at fair value using net asset value per share (or its practical expedient). For additional information, refer to the following sections within Item 8. "Financial Statements and Supplementary Data." of this Form 10-K: (i) item (d) of Note 2. "Summary of Significant Accounting Policies" for descriptions of the levels within the fair value hierarchy and the valuation techniques used for our Level 3 securities and (ii) Note 7. "Fair Value Measurements" for quantitative information on the unobservable inputs in our securities measured using Level 3 inputs.

Allowance for Credit Losses on AFS Fixed Income Securities

When we do not intend to sell fixed income securities in an unrealized loss position, we record an allowance for credit losses for the portion of the unrealized loss related to an expected credit loss. We estimate expected credit losses on these securities by performing a risk-adjusted discounted cash flow ("DCF"). The allowance for credit losses is the excess of amortized cost over the greater of (i) our estimate of the present value of expected future cash flows or (ii) fair value. The allowance for credit losses cannot exceed the unrealized loss, and therefore it may fluctuate with changes in the security's fair value. We also consider the need to record losses on securities in an unrealized loss position for which we have the intent to sell. If we determine that we have the intent or likely requirement to sell the security, we write down its amortized cost to its fair value.

We analyze unrealized losses for credit loss in accordance with our existing accounting policy, which includes performing DCF analyses at the lot level and analyzing the resulting DCFs using various economic scenarios. In performing these DCF analyses, we calculate the present value of future cash flows using various models specific to the major security types in our portfolio. These models use security-specific information and forecasted macroeconomic data to determine possible expected credit loss scenarios based on projected economic changes. The forecasted economic data incorporated into the models is based on the Federal Reserve Board’s annual supervisory stress test review of certain large banks and financial institutions.

We also can incorporate internally-developed forecast information into the models as we deem appropriate. In developing our best estimate of the allowance for credit losses, we consider our outlook for the probability of the various scenarios.

Based on these analyses, we recorded an allowance for credit losses on our AFS fixed income securities portfolio of $31.3 million at December 31, 2025, and $31.9 million at December 31, 2024. If the security-specific and macroeconomic assumptions in our DCF analyses or our outlook on the occurrence probability of our DCF model scenarios were to change, our allowance for credit losses and the resulting credit loss expense or benefit would negatively or positively impact our results of operations. Factors considered in determining the allowance for credit losses require significant judgment, including our evaluation of the security's projected cash flow stream.

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For additional information regarding our allowance for credit losses on AFS fixed income securities, see item (c) of Note 2. "Summary of Significant Accounting Policies" and item (i) of Note 5. "Investments" within Item 8. "Financial Statements and Supplementary Data." of this Form 10-K, respectively.

Reinsurance

Reinsurance recoverables on paid and unpaid loss and loss expense represent our estimates of the amounts we will recover from reinsurers. Each reinsurance contract is analyzed to ensure sufficient risk is transferred to record the transactions appropriately as reinsurance in the Financial Statements. Amounts recovered from reinsurers are recognized as assets contemporaneously and in a manner consistent with the paid and unpaid losses associated with the underlying policies. An allowance for credit losses on our reinsurance recoverable balance is recorded based on an evaluation of balances due from reinsurers and other available information, including collateral we hold under the terms and conditions of the underlying agreements. Reinsurers often purchase and rely on their retrocessional reinsurance programs to manage their capital positions and improve their financial strength ratings. Details about retrocessional reinsurance programs are not always transparent, making it difficult to assess our reinsurers' exposure to counterparty credit risk. Other factors impact our reinsurer's credit quality, such as their reserve adequacy, investment portfolio, regulatory capital position, catastrophe aggregations, and risk management practices. In addition, contractual language interpretations and willingness to pay valid claims can impact our allowance for estimated uncollectible reinsurance. Our allowance for estimated uncollectible reinsurance was $2.0 million at both December 31, 2025 and December 31, 2024. We continually monitor developments that may impact recoverability from our reinsurers, for which we have contractual remedies, if necessary. For further information regarding reinsurance, see the "Reinsurance" section below in "Results of Operations and Related Information by Segment" and Note 9. "Reinsurance" in Item 8. "Financial Statements and Supplementary Data." of this Form 10-K.

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Financial Highlights of Results for Years Ended December 31, 2025, 2024, and 20231

1Refer to the Glossary of Terms attached to this Form 10-K as Exhibit 99.1 for definitions of terms used in this financial review.

2Non-GAAP operating income (loss), non-GAAP operating income (loss) per diluted common share, and non-GAAP operating ROE are comparable to net income (loss) available to common stockholders, net income (loss) available to common stockholders per diluted common share, and ROE, respectively, but exclude after tax net realized and unrealized gains and losses on investments included in net income (loss). Adjusted book value per common share is comparable to book value per common share, but excludes total after-tax unrealized gains and losses on investments included in accumulated other comprehensive income (loss). These non-GAAP measures are important financial measures used by us, analysts, and investors because the timing of realized investment gains and losses on securities in any given period is largely discretionary. In addition, net realized and unrealized investment gains and losses on investments could distort the analysis of trends.

Reconciliations of our GAAP to non-GAAP measures are provided in the tables below:

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The components of our ROE and non-GAAP operating ROE are as follows:

In 2025, we generated an ROE of 14.4% and a non-GAAP operating ROE of 14.2%, driven by strong investment income and improved underwriting performance. This year's results exceeded our target non-GAAP operating ROE of 12%. The improvement in net investment income earned in 2025 compared to 2024 was primarily driven by active portfolio management, operating cash flow deployment, and the proceeds from our 5.9% Senior Notes in the first quarter of 2025. All three insurance segments also contributed to the higher ROE this year compared to last. After-tax underwriting income of $107.4 million this year compared to an underwriting loss of $104.7 million last year was driven by lower catastrophe losses and lower prior year casualty reserve development, partially offset by higher current year loss costs. Underwriting results for 2025 included $90 million of unfavorable prior year casualty reserve development, down from $311 million in 2024.

For additional qualitative discussion on prior year casualty reserve development, refer to the insurance segment sections below.

Outlook

In 2025, we delivered a double-digit operating ROE of 14.2%, exceeding our ten-year average operating ROE of 12.1%. Our performance drove an 18% increase in book value per share in 2025, and we returned $182 million to common stockholders through regular dividends and opportunistic share repurchases. Selective celebrates its 100th anniversary in 2026, and we are proud of our history, the work our employees do, and the value we deliver our policyholders, distribution partners, and shareholders. To ensure our continued success, we remain focused on a set of key priorities across the company to drive future success, including:

•Relentlessly improving on the fundamentals across risk selection, individual policy pricing, and claims outcomes. Risk selection, granular and accurate risk pricing, and prompt, fair claims adjudication are foundational capabilities we have built over many decades and remain focused on today.

•Diversifying revenue and income within and across our three insurance segments. Growth levers include achieving greater market share and segment diversification in Standard Commercial Lines, potential geographic expansion in Standard Personal Lines, and increasing our product and distribution capabilities in E&S Lines and other specialty lines.

•Further leveraging the use of data analytics and technology, including general-purpose, industry-trained, and agentic artificial intelligence solutions, to drive operational efficiency and improved underwriting and claim outcomes. Technology investments are critical to ensure efficiency and scale. To enhance underwriting scalability, risk management, and claims handling, we are actively developing and executing artificial intelligence use cases. We have also made considerable progress in modernizing our policy acquisition and claims systems. For example, system

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enhancements in our E&S Lines segment have created significant operational efficiency, with the segment’s premium production increasing significantly despite limited headcount growth.

We remain committed to making strategic investments that fuel continued growth, innovation, and performance excellence. As we position ourselves for the future, we have several strategies to grow market share profitably:

•In our existing footprint, we are focused on growing with existing partners and strategically appointing new agency locations. During 2025, we had a net increase of approximately 100 agency locations, and we had a net increase of 200 agency locations in 2024.

•Careful and deliberate geographic expansion. Since 2017, we have added fourteen states to our Standard Commercial Lines footprint, including Kansas in 2025. In 2025, these expansion states produced $430 million in premium, representing approximately 9% of total NPW and approximately 1% marginal total premium growth. We expect to write new business in Montana and Wyoming by the end of 2026.

For 2026, our full-year expectations are as follows:

•A GAAP combined ratio of 96.5% to 97.5%, including net catastrophe losses of 6 points. Our combined ratio estimate assumes no prior year casualty reserve development, as we record our best estimate each quarter. We do not make assumptions about future reserve development;

•After-tax net investment income of $465 million;

•An overall effective tax rate of 21.5%; and

•Weighted average shares of 61 million on a fully diluted basis. We do not make assumptions about future share repurchases under our existing authorization.

Results of Operations and Related Information by Segment

Insurance Operations

The following table provides quantitative information for analyzing the combined ratio:

The NPW growth of 5% in 2025 compared to 2024 included:

Our NPW growth in 2025 also benefited from exposure growth on renewal policies. The impacts of exposure growth and renewal pure price increases were partially offset by a modest decrease in policy count and lower new business.

The increase in NPE in 2025 compared to 2024 resulted from the same impacts to NPW described above.

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Loss and Loss Expenses

The following table provides quantitative information for analyzing loss and loss expense incurred:

Prior Year Casualty Reserve Development and Current Year Casualty Loss Costs

Details of the prior year casualty reserve development by reportable segment and line of business were as follows:

The loss and loss expense ratio improved 6.0 points in 2025 compared to 2024, including a 5.2-point improvement in net unfavorable prior year casualty reserve development, driven by improved severities in our workers compensation line of business in accident year 2022 and prior, combined with a stabilization of loss trends in our general liability and E&S casualty lines of business. Even with the year-over-year improvement in the development, these two lines reflected increased severity in recent prior accident years due to the impact of ongoing, broad-based social inflation. However, this improvement was partially offset by a higher amount of prior year development in commercial and personal automobile, as we experienced a re-acceleration of severity growth. For commercial automobile, the unfavorable prior year development was related to accident years 2022 through 2024, with 2024 being the primary driver. For personal automobile, accident year 2024 was the primary driver of the unfavorable prior year development.

In 2024, unfavorable prior year casualty reserve development was $311 million, or 7.1 combined ratio points. This included $316 million in the general liability line of business in our Standard Commercial Lines segment for accident years 2020 and subsequent, with most of the actions for accident years 2022 and 2023. Social inflation drove this development.

Current year loss costs were 3.5-points higher in 2025 compared to 2024, driven by elevated severity trend assumptions attributable to social inflation on our general liability and E&S casualty lines of business, and responding to prior year development in our commercial and personal automobile line of business.

For additional qualitative discussion on prior-year casualty reserve development and current-year casualty loss costs, refer to the insurance segment sections below.

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Property Losses

Net catastrophe and non-catastrophe property losses were 4.3 points lower in the aggregate in 2025 compared to 2024. Lower net catastrophe losses were due to a lower frequency and severity of storms that impacted our footprint. Lower non-catastrophe property loss and loss expenses reflected (i) the earned impact of higher renewal pure price increases in 2025, (ii) lower claim frequencies, and (iii) variability from period to period of non-catastrophe losses.

For additional qualitative discussion on non-catastrophe property loss and loss expenses, refer to the insurance segment sections below.

Standard Commercial Lines Segment

NPW and NPE growth in 2025 compared to 2024 included renewal pure price increases and exposure growth on renewal policies, partially offset by lower retention as a result of underwriting actions.

Loss and Loss Expenses

The following table provides quantitative information for analyzing loss and loss expense incurred:

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Prior Year Casualty Reserve Development and Current Year Casualty Loss Costs

Details of the prior year casualty reserve development by line of business were as follows:

The loss and loss expense ratio decreased 6.1 points in 2025 compared to 2024, including a 6.6-point improvement in net unfavorable prior year casualty reserve development. The increase in current year loss costs compared to 2024 was primarily driven by elevated severity trend assumptions attributable to social inflation on our general liability line of business, and responding to prior year development in our commercial automobile line of business.

Refer to the line of business sections below for qualitative discussion of the significant drivers of unfavorable prior year casualty reserve development and current-year casualty loss costs.

Property Losses

Net catastrophe and non-catastrophe property losses were 3.0 points lower in the aggregate in 2025 compared to 2024. This was primarily driven by net catastrophe losses, which were 2.7 points lower than last year, driven by a lower frequency of wind, winter storm, and hurricane events.

Refer to the line of business sections below for qualitative discussion of the significant drivers of non-catastrophe property loss and loss expenses.

The following is a discussion of our most significant Standard Commercial Lines of business:

1n/a: not applicable.

NPW grew 7% in 2025 compared to 2024, benefiting from renewal pure price increases and renewal exposure growth.

The combined ratio was 17.8 points lower in 2025 compared to 2024, primarily driven by the following:

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We recorded unfavorable prior-year casualty reserve development of $40 million in 2025, compared to $316 million in 2024. We attribute the unfavorable development in both periods to the ongoing, broad-based social inflationary factors impacting this line of business. Development in 2025 was driven by increased severities in accident years 2022 and 2023. Development in 2024 was driven by increased severities in accident years 2020 through 2023.

The general liability line of business has experienced a long-term trend of meaningful severity increases, partially offset by claim frequency decreases. Prior-year severities developed adversely, impacting our view of more recent accident years in 2024 and 2025. We attribute the increased severities to elevated social inflation, which we view as an industry dynamic characterized by higher claimant propensity for attorney representation and litigation, longer settlement times, and higher settlement values. Certain jurisdictions with expanded liability theories and higher damage awards pose increased challenges. We are closely monitoring these jurisdictions and the broader trends across our business.

We experienced a 6.9-point increase in current-year casualty loss costs in 2025 compared to 2024, primarily driven by increased loss trend expectations and higher prior-year severity assumptions related to the impacts of social inflation.

We believe that social inflation and elevated loss trends continue to support an elevated near-term pricing environment. In response, we have a heightened focus on prudent underwriting and appropriate pricing. Our renewal pure price increase in this line of business was 11.3% in 2025, up from 8.6% in 2024. In sectors and jurisdictions where market pricing does not align with our view of rate need, we are taking targeted underwriting actions, including (i) revising underwriting guidelines, (ii) tightening coverage offerings, and (iii) reducing writings.

1n/a: not applicable.

NPW grew 6% in 2025 compared to 2024, benefiting from renewal pure price increases, partially offset by lower retention.

The combined ratio was 10.8 points higher in 2025 compared to 2024, primarily driven by the following:

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We recorded $125 million of unfavorable prior year casualty reserve development in 2025, driven by increased severities in accident years 2022 through 2024, with 2024 being the primary driver. Current year casualty loss costs were higher in 2025 compared to the same prior-year periods, in reaction to the unfavorable prior-year casualty reserve development.

Partially offsetting the unfavorable combined ratio drivers mentioned above, non-catastrophe property loss and loss expenses in 2025 were lower compared to 2024, primarily due to (i) the earned impact of higher renewal pure price increases in 2025, and (ii) lower claim frequencies.

1includes Inland Marine.

2n/a: not applicable.

NPW grew 7% in 2025 compared to 2024, benefiting from renewal pure price increases and exposure growth on renewal policies.

The combined ratio was 11.9 points lower in 2025 compared to 2024, primarily driven by the following:

Net catastrophe losses were meaningfully lower in 2025 compared to 2024, driven by a lower frequency of wind, winter storm, and hurricane events.

1n/a: not applicable.

NPW decreased 8% in 2025 compared to 2024, primarily due to renewal pure price decreases and a reduction in direct new business.

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The combined ratio was 6.8 points lower in 2025 compared to 2024, primarily due to the following:

The favorable prior year casualty reserve development in 2025 and 2024 was primarily due to improved loss severities driven by continued lower medical cost trends. The favorable development in 2025 and 2024 was related to improved loss severities in accident years 2022 and prior.

In addition, the combined ratio was adversely impacted by an increase in current year casualty loss costs of 8.0 points in 2025, primarily driven by negative rate changes and increased loss trends. These rate level reductions are driven by continued decreases in workers compensation rating bureau loss costs, which form the basis for our filed rating plans, and heavily influence marketplace pricing for this line of business.

Standard Personal Lines Segment

NPW decreased 8% in 2025 compared to 2024, primarily due to lower direct new business. New business decreased 37% in 2025 compared to 2024. The reduction in direct new business premiums was primarily due to a 50% decline in new policy counts in 2025 compared to 2024. The reduction in new policy counts and new business premiums was driven by (i) market conditions, including a challenging rate environment in New Jersey and South Carolina, (ii) competition in other states due to our recent rate activity, and (iii) focusing on our target mass affluent market. We have received regulatory approvals for increased rate levels in most of our footprint states and are focused on growth where we believe our rates are adequate.

The following table depicts our reductions in direct new business and retention for 2025 and 2024:

1Excludes our flood direct premiums written, which is 100% ceded to the NFIP and therefore, has no impact on our NPW.

The change in NPE in 2025 compared to 2024 was driven by the same impacts on NPW described above.

Underwriting results for this segment improved in 2025 compared to 2024 as we are obtaining positive results from the actions we took to refine our pricing factors and prioritize rate filings to mitigate inflationary impacts. Our more significant rate increases began to take effect early in 2023, increased in number and magnitude throughout 2024, and remained strong in 2025, albeit moderately lower than in 2024. We expect these rates to continue outpacing loss trends in 2026, but at lower levels than those seen in 2024 and 2025. Through our actions, we achieved renewal pure prices increases of 18.6% in 2025. Additionally,

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we have continued to focus our efforts on our target mass affluent market. In 2025, target business grew 10%, with nearly all new business being in our target market.

Loss and Loss Expenses

The following table provides quantitative information for analyzing loss and loss expense incurred:

Property Losses

The loss and loss expense ratio decreased 8.5 points in 2025 compared to 2024, primarily driven by net catastrophe and non-catastrophe property losses, which reduced the loss and loss expense ratio by 13.5 points in the aggregate in 2025 compared to 2024. Net catastrophe losses reflected lower frequency and severity of weather-related catastrophe events this year compared to last year. Non-catastrophe property losses were lower in 2025 compared to 2024 due to (i) the earned impact of renewal pure price increases in 2025, (ii) lower claim frequencies, and (iii) variability from period to period of non-catastrophe losses.

Prior Year Casualty Reserve Development and Current Year Casualty Loss Costs

Details of the prior year casualty reserve development by line of business were as follows:

Prior year casualty reserve development in 2025 included $15.0 million of unfavorable development in personal automobile, primarily driven by increased loss severities in the 2024 accident year related to the New Jersey portfolio. Prior year casualty reserve development in 2024 included $10.0 million of unfavorable development in personal automobile, primarily driven by increased loss severities in accident years 2022 and 2023. This was partially offset by $5.0 million of favorable development in homeowners, primarily due to lower loss severities in accident years 2021 and prior.

Current year casualty loss costs increased 2.5 points in 2025 compared to 2024. Prior-year severities developed adversely over the course of 2024 and 2025, impacting our view of the current year loss costs for 2025. This resulted in higher current-year casualty loss costs this year compared to last.

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E&S Lines Segment