Five9, Inc. (FIVN) Business

ITEM 1. Business

Overview

Five9 is a leading provider of intelligent customer experience, or CX, platform for enterprise contact centers. With a foundation in our cloud-native solution, Five9 is now evolving into an AI-native CX platform, empowering enterprises to scale seamlessly, innovate faster, and deliver enhanced customer experiences as the market opportunity continues to expand. Our reliable, secure, and scalable Intelligent CX Platform, powered by our Five9 Genius AI suite, delivers a comprehensive suite of easy-to-use applications that enable the breadth of customer service, sales, and marketing functions. We have become an established leader in the AI-powered CX market with more than 3,000 customers. We believe our end-to-end, AI-powered CX platform creates a significant advantage by orchestrating interactions across all channels throughout the customer journey.

We believe there are two key industry trends driving growth in the cloud contact center market.

First is the increasing adoption of cloud-based solutions within companies around the world, which is creating strong demand for integrated cloud contact center software solutions. Cloud contact center solutions offer the functionality, reliability, scalability and security required by large, complex enterprise contact centers. Furthermore, organizations periodically refresh their on-premises contact center systems, which provides an opportunity for cloud solutions to replace legacy on-premises contact center systems. On-premises systems require large up-front investments, long deployment cycles, and are burdensome to scale and maintain. These systems are also often inflexible, complex, and require significant duplication of effort and integration across multiple sites. AI technologies generally require cloud deployment and, therefore, provide additional incentives for customers to migrate away from their legacy on-premises solutions. In addition, agents increasingly work remotely, which presents a challenge to on-premises based systems that, by design, provide capabilities within a specific physical location. This creates substantial challenges for customers with on-premises contact center systems. As a result, cloud contact center software solutions are continuing to replace legacy on-premises contact center systems. These cloud contact center systems provide organizations with the agility to adapt to rapidly evolving customer demands and leverage innovative functionalities to improve engagement.

Second is advancements in artificial intelligence, or AI. AI is a significant advancement to improve customer experience across self-service, agent assistance, managerial insights, and workflow automation use cases. This often provides significant operational efficiencies and improved business insights and intelligence. The recent advances in Generative AI, including Large Language Models, or LLMs, enable new capabilities in contact centers that were not previously possible. Our Genius AI suite is a comprehensive portfolio of AI solutions that uses Generative AI to power agentic CX. For instance, our agentic AI Agents solution redefines virtual agents, with the power of Generative AI, to deliver a hyper-personalized customer experience, unlocking additional efficiencies with automation. Our AI Summaries capability uses Generative AI to automatically summarize a call, reducing after-call work time. Natural language voice and chat-bots, using Generative AI, provide speech recognition, intent detection, and text-to-speech technologies to quickly and effectively handle mundane contact center tasks, allowing agents to focus on more complex issues. Generative AI technologies are also used in our AI Insights product, which gives customers an understanding of the reasons for customer calls, provides customer sentiment, and call resolution status, with little up-front configuration or setup.

Our solution empowers our customers to harness the value of these two market trends. Comprised of our Intelligent CX Platform and AI capabilities, including agentic AI agents, Agent Assist, Workflow Automation, or WFA, AI Insights, AI Summaries, Workforce Engagement Management, or WEM, and Revenue Execution, our solution allows simultaneous management and optimization of customer interactions across voice, chat, email, web, social media and mobile channels, either directly or through our application programming interfaces, or APIs.

Our Intelligent CX Platform matches each consumer interaction with an appropriate agent resource and delivers relevant consumer data to the agent in real-time through integrations with adjacent enterprise applications, such as CRM software, to optimize the consumer experience and improve agent productivity. Delivered on-demand, our solution ensures customers always have the latest version, and enables them to quickly deploy agents in any geographic location with only a computer, headset and broadband internet connection. Our customers are able to adjust the level of our solutions used to meet their changing contact center volume needs. Unlike legacy on-premises contact center systems, our solution requires limited up-front investment, can be rapidly deployed, and is maintained by us in the cloud.

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The contact center is the system of record for interactions with full conversation history. Our platform serves as a real-time orchestration engine for every customer interaction across all channels, whether it is with a human agent or an AI agent. As a result, our platform is designed to deliver a seamless collaboration between human agents and AI agents, where each interaction strengthens the next. This continuous learning loop compounds over time, creating a powerful data flywheel that drives higher performance, accuracy, and personalization for every customer engagement. We believe this is the structural advantage of our end-to-end AI-powered CX platform.

Our sales model consists of a field sales team that sells our solution into mid-size, enterprise, and Fortune 1000 companies and a telesales team that sells our solution into smaller companies. We have developed a proven, high-velocity, metrics-driven sales and marketing strategy, designed to effectively identify, qualify and close sales opportunities. To complement our go-to-market strategy, we have developed a strategically-built ecosystem of technology alliances, solution providers and system integrator partners, which also provide sales leads, and independent software vendors to help increase awareness of our solution in the market and drive additional sales opportunities with new and existing customers. We have also established, and are continuing to increase, our network of technology solution distributors who provide sales leads and resellers that integrate our solution into their service offerings to new customers. Our partner ecosystem has helped us access new routes to market and increase our penetration in domestic and international markets.

We provide our solution through a software-as-a-service, or SaaS, business model. We generate subscription revenue from our Intelligent CX Platform, and also generate usage-based telephony revenue. We charge our customers monthly subscription fees for access to our solution, primarily based on the number of licenses. Our AI solutions are sold to our customers on a consumption or capacity basis.

Our revenue has consistently grown. For the years ended December 31, 2025, 2024 and 2023, our revenue was $1,149.1 million, $1,041.9 million and $910.5 million, respectively, representing year-over-year growth of 10% and 14%, respectively. We have achieved significant improvement in our net income (losses) in recent periods. We recorded net income (losses) of $39.4 million, $(12.8) million and $(81.8) million for the years ended December 31, 2025, 2024 and 2023. As of December 31, 2025, 2024 and 2023, our total assets were $1,790.1 million, $2,051.2 million and $1,494.6 million, respectively. Our recurring revenue model combined with our Annual Dollar-Based Retention Rate, which was 105% as of December 31, 2025, have enhanced our ability to forecast our financial performance and plan future investments. For a description of how our Annual Dollar-Based Retention Rate is calculated, please refer to ITEM 7 “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in Part II of this Annual Report on Form 10-K.

We operate in a single reportable segment. Please refer to the geographical information for each of the last three years in Note 11 of the notes to our consolidated financial statements. Please refer to the discussion of risks related to our foreign operations in the section entitled “ITEM 1A. Risk Factors.”

Our Solution

We deliver a comprehensive, end-to-end cloud software solution for contact centers. Our solution is designed to enable our customers to increase and improve the efficiency of their operations, increase revenue opportunities and business agility, and provide insights into the behaviors of their workforce and customers as it relates to customer experience. Our platform facilitates this through key capabilities such as interaction routing and prioritization across channels, automation and integration of back and front-end systems and the ability to leverage the power of AI through self-service, agent assistance, management insights, and more. Our solution also empowers agents and supervisors through WEM. A broad range of organizations use our solution to improve customer service and create customer loyalty. These capabilities are offered across a wide variety of engagement channels from chat and SMS to e-mail and voice. Consumers are able to engage using their channel of choice and customers are able to facilitate seamless experiences.

Our agent interface is an intuitive, modern browser-based design that provides easy visualization of customer profiles, context and cross-channel history. Our solution is built on a modern SaaS architecture, leveraging both global data centers and public cloud deployments in a scalable, secure, and redundant manner. Our Intelligent CX Platform is based on a modern micro services-based open enterprise architecture with open APIs and software development kits, or SDKs, to enable customers, partners and developers to integrate our solution into their unique systems. AI is an embedded part of our platform. We provide high quality inbound and outbound voice services leveraging our global network infrastructure with key strategic carrier partnerships, including complex real-time call routing, and a wide range of customer connectivity options for secure and resilient interconnectivity to our network. Our complete end-to-end, omni-channel capabilities include AI Agents, Agent Assist, WFA, AI Insights, AI Summaries, AI Knowledge, WEM, Automatic Call/Contact Distribution, or ACD, with skills-based routing,

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reporting, dashboards, agent and supervisor desktops, outbound dialer, pre-built third-party integrations, quality management, speech and desktop analytics, customer surveys and engagement through chat, email, social and web. Our solution also includes revenue execution capabilities, including outbound campaigns, compliance and out-reach solutions.

Our solution provides the following advantages:

•Rapid implementation, seamless updates and pre-built integrations. Our solution is designed to be deployed quickly and seamlessly with minimal disruption to a customer’s operations. The pre-built integrations with leading CRM and other enterprise applications reduce the complexity and burden of integrating with the customer’s business applications. Our solution is designed to be seamlessly updated so that customers are always operating on the latest version of the software, while maintaining their existing configurations, to ensure minimal disruption to the customer’s contact center operations.

•Highly flexible platform. Our solution provides easy administration, configuration and role-based functionalities for agents, supervisors and administrators, enabling the rapid adjustment of contact center resources to meet a changing mix of contact channels and peaks-and-troughs in contact center volumes.

•Scalable, secure and reliable multi-tenant architecture. Our solution provides organizations of all sizes with robust contact center functionality, scalability, flexibility and security required in the most sophisticated and distributed environments.

Our solution is designed to provide the following key benefits to customers:

•A complete omni-channel solution. Our Intelligent CX Platform offers a comprehensive and rich collection of interaction capabilities including voice, email, SMS, chat, social and more. By offering a collection of services to interact with customers in multiple ways, our customers benefit from closer engagement, improved brand loyalty, and higher repeat purchases by meeting customers where they are.

•Improved customer experience. Our intelligent contact routing and self-service IVA, IVR, and AI Agent capabilities, including pre-built CRM and other integrations, and omnichannel engagement are designed to ensure that consumers have a positive experience. New contacts are quickly routed to an appropriate agent. Using the rich contact history and additional context through integrations with CRM and other applications, agents have immediate access to the most current, relevant and accurate information about the customer, resulting in increased first contact resolutions and a more satisfying experience for the customer.

•Higher agent productivity. Our solution empowers agent productivity and effectiveness by allowing agents to handle both inbound and outbound calls and interact with customers across multiple digital engagement channels, including voice, chat, email, web, social media and mobile. Our solution enables agents to switch between media channels through an easy-to-use, unified interface that provides agents with all of the relevant content and tools needed to respond to customer needs. Furthermore, our Genius AI suite of solutions are designed to enable agent efficiency and cost reductions, including through the utilization of LLMs and natural language processing, or NLP.

•Enhanced end-to-end visibility. Our solution provides contact center management, operations staff, quality team and executive leadership with a complete view of contact center performance through a comprehensive set of historical reports, real-time dashboards, and quality and performance management tools. Customers can also extract reporting data from our solution for further analysis using a spreadsheet application or using the sophistication of an enterprise business intelligence application. Our advanced reporting solution enables us to connect to external data sources such as ACDs, WEM platforms, CRM solutions, and many more pre-built integrations. In addition, the combination of our reporting and analytic solutions enable us to connect disparate reporting and intelligence data sources, providing an organization-wide view of customer engagement performance and allowing customers to quickly address changing circumstances.

•Global voice & telecommunications infrastructure. Our solution integrates a global voice network and telecommunications foundation with cloud-based software to support reliable, scalable, and compliant customer engagement across multiple geographies. Our solution is built on a distributed network architecture with redundant routing, regional points of presence, and diverse carrier interconnections, and is complemented by extensive customer self-service capabilities that enable customers to provision services, manage numbers and routing, configure policies, and control call flows without direct provider intervention. Customers are also provided with embedded observability, monitoring, and alerting capabilities that offer

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visibility into call performance, traffic patterns, and service health, enabling proactive management of their operations.

•Greater operational efficiency. Our solution provides contact center managers and supervisors with significant visibility into their agents’ productivity and effectiveness and the performance of their inbound queues and outbound campaigns. Our solution has robust intelligence and analytics capabilities to help supervisors optimize operations and campaigns in real-time to drive increased efficiency. Additionally, we believe our Genius AI suite provides efficiencies across our customers’ overall operations.

•Compelling value proposition. We provide a unified cloud-based software platform for contact center operations, including software applications, technology infrastructure, maintenance, monitoring, storage, security, customer support and upgrades, which enables our customers to simplify their technology infrastructure and streamline IT costs. We manage upgrades and deployments remotely, resulting in lower total cost of operations relative to legacy on-premises contact center systems that often require in-house technical support staff.

•Implementing AI successfully. We provide our AI Blueprint program to assist customers with strategic planning and implementation of powerful solutions from our Genius AI suite. Our consultative approach to identifying business opportunities for enhancement and growth, leveraging our Genius AI suite of solutions is helping companies take advantage of these advanced technologies to improve CX and increase customer satisfaction.

Our Competitive Strengths

We believe that our position as a leading provider of cloud contact center software results from several key competitive strengths, including:

•Global Cloud-based, AI-infused, enterprise-grade platform and end-to-end application suite. We deliver a cloud-based, enterprise-grade, AI-infused platform and applications suite with multi-channel capabilities that allows our customers to manage their entire contact center operation. Our highly reliable, scalable, secure and multi-tenant architecture enables us to serve large multi-national enterprises with complex contact center requirements, as well as smaller organizations, all from our platform comprised of globally distributed physical data centers and public cloud deployments. We also have investments in a dedicated U.S.-based data center deployment to enable us to support any Federal Risk and Authorization Management Program, or FedRAMP, customers in the future.

•Customer success with our consultative approach. Our high-touch engagement model for larger implementations accelerates agent activation and targets desired business outcomes by leveraging a proven lifecycle approach including detailed discovery, design, testing, training and optimization. Through the use of proprietary tools and processes that have been refined over thousands of customers, we can also efficiently meet the needs of our smaller customers. We offer flexibility and integrate with a number of leading CRM vendors, including Microsoft Corporation, or Microsoft, Oracle Corporation, or Oracle, Salesforce.com, Inc., or Salesforce, ServiceNow, Inc., or ServiceNow, Zendesk, Inc., or Zendesk, among others. We also offer integrations into UC partners such as Microsoft Teams, Nextiva, RingCentral, Zoom Video Communications, or Zoom, and others. We combine these comprehensive integrations with out-of-the-box application adapters that allow our customers to easily build workflow integrations without the need for dedicated developers. Once operational, we offer a high-touch premium support service where we assign a technical account manager who has intimate knowledge of the customers’ operations so we can quickly resolve issues and fine-tune the solution. In addition, we assign customer success representatives to every customer. These customer success representatives build deep relationships with our customers to help maximize the value of our platform. As a result, our customers’ contact centers become fully operational faster and they recognize time to value quicker than legacy on-premises contact center systems.

•Reliable, secure, compliant and scalable platform. Our platform delivers what we believe is industry-leading reliability utilizing public and private cloud technology; cybersecurity using a defense-in-depth approach; scalability to accommodate the requirements of larger customers; and legal and regulatory compliance features designed to assist our customers in complying with applicable laws, regulations and industry standards.

•Proven, repeatable and scalable go-to-market model. We engage with our customers through a highly scalable and metrics-driven sales and marketing organization that effectively identifies, qualifies and closes

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sales opportunities. The deep domain expertise of our field sales team is instrumental in selling to larger opportunities, and our highly efficient telesales model enables us to cost-effectively identify, qualify and close a high volume of smaller opportunities. Our ecosystem of technology, system integrator and channel partners increases awareness of our solution and helps generate new sales opportunities. We believe our go-to-market model gives us an efficient and effective means of targeting organizations of all sizes.

•Established market presence and a large, diverse customer base. We have a large, diverse customer base of over 3,000 organizations across multiple industries. We believe our customers view us as a key strategic solution provider. The performance, reliability, ease-of-use and comprehensive nature of our solution has resulted in high customer retention.

•Extensive partner ecosystem. We have built a robust ecosystem of partners including a variety of leading CRM software vendors such as Microsoft, Oracle, Salesforce, ServiceNow and Zendesk; WEM vendors such as Calabrio, Inc., or Calabrio, and Verint Systems Inc., or Verint; unified communications vendors such as Microsoft Teams, RingCentral and Zoom; system integrators such as Accenture PLC, Deloitte Consulting LLP, Ernst & Young, IBM, Kyndryl, Inc., PwC LLP and Slalom Consulting, LLC; technology solution distributors such as Avant, LLC, Intelysis, Sandler Partners, Telarus, Amplix and Bridgepoint Technologies; value-added resellers such as AT&T Inc., Babble Cloud, British Telecom, Connect Managed Services (UK) Limited, CDW Corporation, NWN Carousel, Opus Technology and TELUS Communications; software vendors such as Cresta AI, Pindrop, Blackchair, Level AI, Calabrio and its recently acquired subsidiary, Verint; and telephony providers. We believe this partner ecosystem has enabled us to increase our brand awareness and enhance the functionality and value of our solution for our customers.

•Enabling Network and Telecommunications Services. Our global network and telecommunications capabilities represent a competitive strength because we directly operate and manage critical elements of our voice infrastructure, service delivery workflows, and telecom integrations, rather than relying primarily on third-party aggregation. This level of operational control allows us to optimize routing, manage capacity, respond to incidents, and evolve our network while deploying these capabilities with our customers through integrated self-service, monitoring, and alerting tools that provide real-time insight into service performance. By unifying telecom engineering, operations, regulatory expertise, and customer-facing controls within a single operating model, we are able to support complex, high-volume, and multi-region deployments, while adapting to changing customer requirements, carrier dynamics, and regulatory environments, which we believe enhances our ability to compete effectively in the enterprise contact center market.

•Focus on innovation and thought leadership. Since our inception, we have been an innovator of intelligent cloud contact center software. Our investment in research and development has driven our growth and enabled us to deliver an Intelligent CX Platform with the capabilities and functionality to power the most complex contact centers. We strive to be a thought leader in our industry, identifying and developing cloud capabilities to transform traditional contact center operations into customer experience centers of excellence. Contact centers are a rich source of the contextual data that powers AI, from interaction data such as call transcripts to customer data from extensive integrations to back office systems, as well as brand information. Recent advances in Generative AI enable us to deliver even more innovation by integrating it deep into our Intelligent CX Platform. We believe that AI, and Generative AI in particular, will continue to profoundly impact how businesses deliver experiences to their customers.

Customers

We have a large, diverse and global customer base comprised of more than 3,000 organizations as of December 31, 2025, with no single customer representing more than 10% of our revenues in 2025, 2024 or 2023. Our customer base spans organizations of all sizes across multiple industries, including banking and financial services, business process outsourcers, retail, healthcare, technology and education.

Sales and Marketing

Marketing. To build customer awareness and adoption of our solution, our lead generation activities consist of a mix of organic activities such as social, digital presence and search engine optimization, and paid programs such as search engine marketing, internet advertising, digital marketing campaigns, content syndication, presence at industry events and trade shows, co-marketing with strategic partners, account-based marketing, customer referrals and other promotional campaigns. In addition, our industry analyst, press and media outreach programs, and web site marketing initiatives are designed to build brand awareness and preference for our solution. We offer online

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self-service demos and instructional videos to help prospective customers learn about the capabilities and functionality of our cloud platform. We also offer proof of concept service packages and trial opportunities, which include return-on-investment analyses conducted by third parties, to allow prospects to experience the quality and ease-of-use of our cloud solution and quantify the potential benefits of our deployment model.

Direct Sales. Our sales model consists of a field sales team that sells our solution into larger opportunities and a telesales team that sells our solution into smaller opportunities. Our field and telesales teams are also responsible for selling to existing customers that may renew their subscriptions, increase the number of licenses using our cloud solution, add new applications from our solution and expand the deployment of our solution across their contact centers.

Indirect Sales. We have cultivated strong partner relationships with technology solution distributors, global system integrators and resellers to drive sales of our solution. We have established, and continue to increase, our network of technology solution distributors, which provide sales leads, global system integrators, which also provide sales leads and help integrate our solution with our customer systems, and resellers, which sell our solution to new customers. This network has helped us attract additional customers, and we continue to empower these partnerships to participate in the delivery of our solution and extend the total customer value gained from unique integrated value propositions.

Professional Services

We provide professional services to assist our customers in implementing and optimizing our solution. These services include application configuration, system integrations, custom development, AI consulting, and education and training. Customers can either use our team for implementing our solution, perform these services themselves, engage one of our certified implementation partners, or engage their own third-party service provider.

Research and Development

Our ability to compete depends in large part on our continuous commitment to research and development and our ability to improve the functionality of, and add new features to, our Intelligent CX Platform. Our core research and development center is based in our San Ramon, California headquarters, with additional engineers located in Australia, Portugal, and India, which international locations allow us to benefit from lower cost and highly skilled software developers. Our engineering team has deep software and telecommunications skills, and works closely with our sales team to identify our customers’ product requirements. In addition, continuous interactions with our partners enable our engineers to enhance the usability and performance of our platform and its integration with best-in-class CRM and other business applications and telephony technologies.

Technology and Operations

Our highly reliable, secure, compliant, and scalable cloud platform is the result of our extensive research, development, customer engagement and operational experience. Our platform is comprised of in-house developed intellectual property, open source products and commercially available hardware and software. Our platform is designed to be redundant. We believe that all components can be upgraded, expanded or replaced with minimal or no interruption in service.

We currently deliver our services from third-party co-location data center facilities located in the United States, the United Kingdom, Europe and Australia and from public cloud locations in Canada, the United Kingdom, Europe and India. We also host some of our voice services on the public cloud in Europe, Asia, South America, and Australia. Our infrastructure, including our third-party co-location facilities, is designed to support real-time critical telecommunications, applications and operational support systems. Our infrastructure is built with redundant, fault-tolerant components divided into distinct security zones forming protective layers for our applications and customer data.

We have designed and maintain an operations, capacity and security program to monitor and maintain our platform, ensure efficient utilization of our platform capacity and protect against security threats or data breaches. Our operations team monitors our data centers for potential performance issues, unauthorized attempts to access secure data or applications and the overall integrity of the platform.

Competition

The market for contact center software is fragmented, highly competitive and rapidly evolving. The proliferation of different channels of engagement is driving changes in contact center technology, as customers

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expect companies to give them the option of seamless communication across all channels without losing the overall context of customer interactions according to their preferences and needs. More recently, the advent of Generative AI and related technologies has prompted an acceleration in the actual and expected adoption of AI solutions for customer self-service, agent assistance, and management of contact center operations. Combined with the disruptive nature of the cloud in the contact center, this has resulted in competitors who come from different market and product heritages, and who vary in size, breadth, and scope of products and services offered. We currently compete with large legacy vendors that offer on-premises contact center systems, such as Avaya Inc., or Avaya, and Cisco Systems, Inc., or Cisco. These legacy telephony vendors are increasingly supplementing their traditional on-premises contact center systems with competing cloud offerings, through a combination of acquisitions, partnerships, and in-house development. Additionally, we compete with vendors that historically provided other contact center services and technologies and expanded to offer cloud contact center software such as Genesys Telecommunications Laboratories, Inc., or Genesys, and NICE Ltd., or NICE. We also face competition from many smaller contact center service providers such as Content Guru and Talkdesk, as well as vendors offering both unified communications and contact center solutions such as RingCentral and Zoom. In addition, Amazon.com, Inc., or Amazon, Twilio Inc., or Twilio, and Microsoft, have introduced solutions aimed at companies who wish to build their own contact centers and/or contact center components with developers. In addition, CRM vendors are increasingly offering features and functionality, including AI contact center solutions, that were traditionally provided by contact center service providers. CRM and customer experience vendors also continue to partner with contact center service providers to provide integrated solutions and may, in the future, acquire competitive contact center service providers. We also compete with new market entrants in AI that offer Generative AI solutions that compete as point products in the market.

Our actual and potential competitors may enjoy competitive advantages over us, including greater name recognition, longer operating histories, broader product offerings, larger marketing and product development budgets, as well as greater financial and technical resources. With the introduction of new technologies and market entrants, we expect competition to continue to intensify in the future. Our recent, and any future, acquisitions will subject us to new competitors and cause us to face additional and different competition in the markets served by these businesses. We believe the principal competitive factors in our market include:

•breadth and depth of solution features, including AI;

•reliability, scalability and quality of the platform;

•ease and speed of deployment;

•ease of application administration and use;

•level of customer satisfaction;

•domain expertise in contact center operations;

•integration with third-party applications;

•ability to quickly adapt and upgrade to new and evolving technologies, including AI;

•pricing;

•ability to quickly adjust service levels based on business requirements;

•breadth and domain expertise of the sales, marketing and support organization;

•ability to keep pace with customer requirements;

•extent and efficiency of professional services;

•ability to offer multiple channels of engagement; and

•size and financial stability.

We believe we currently compete effectively with respect to each of the factors identified above.

Intellectual Property

We rely on a combination of patent, copyright, and trade secret laws in the U.S. and other jurisdictions, as well as license agreements, confidentiality agreements and other contractual protections, to protect our proprietary technology. We also rely on a number of registered and unregistered trademarks to protect our brand. In addition, we require our employees and independent contractors involved in development of intellectual property to enter into agreements acknowledging that all works, or other intellectual property generated or conceived by them on our

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behalf, are our property, and assigning to us any rights, including intellectual property rights, that they may claim or otherwise have in those works or property, to the extent allowable under applicable law.

As of December 31, 2025, our intellectual property portfolio included 9 registered U.S. trademarks, 2 pending U.S. trademark applications, 26 issued U.S. patents, 4 pending U.S. patent applications and 1 registered U.S. copyright. As of December 31, 2025, outside the U.S. we also had 27 trademark registrations across various countries, 2 pending trademark applications, 5 issued patents and 3 pending international national phase patent applications. There are no Patent Cooperation Treaty, or PCT, patent applications. The expiration dates of our issued patents range from 2030 to 2044. In general, our patents and patent applications apply to aspects of our Intelligent CX Platform.

We are also a party to various license agreements with third parties that typically grant us the right to use certain third-party technology in conjunction with our solution. We expect that software and other applications in our industry may be subject to third-party infringement claims as the number of competitors grows and the functionality of applications in different industry segments overlaps. Any of these third parties might make a claim of infringement against us at any time.

Seasonality

We believe that there are seasonal factors that cause our revenues in the first half of a year to be lower than our revenues in the second half of a year. During 2025, 2024 and 2023, 51%, 52%, and 52% of our total revenues were generated in the second half of each year. We believe this is due to increased activities in retail, healthcare and education in the second half of each year.

Employees and Human Capital Resources

Our employees and the culture we have established are the key to our success. As of December 31, 2025, we had 2,910 full-time employees. 43% of our employees are in various cost of revenue functions, 25% in research and development, 20% in sales and marketing and 12% in general and administrative.

The key human capital measures and objectives that we focus on in managing our business, and creating an environment where all of our employees can thrive, are maintaining our company values, creating an inclusive environment with a broad base of skill sets and experiences, our total rewards philosophy, our talent development, and our employees’ safety and wellness.

Five9 Values - Bringing Passion and Purpose

At Five9, we are focused on delivering success for our customers, partners and employees. Living our values everyday results in a unique and powerful “winning culture” in which every member on our team is passionately committed to achieve collective success. This powerful team-first culture enables us to overcome obstacles and win year after year, while enjoying the journey together.

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Our Five9 values are woven throughout the entire employee lifecycle and used in the interview process to ensure we hire candidates who have values that align with ours. These values are a key element of our semi-annual employee performance self-reflection cycle, where our leaders request that employees share how they have lived our values. In addition, we periodically celebrate employees that live our values through recognition and rewards. We introduce new employees to our values during new hire orientation and our values are visible in employee resource pages.

We regularly gather employee feedback to better understand the employee experience and identify opportunities to continuously strengthen our culture. In our most recent survey in 2025, 83% of our employees participated and our engagement score was 72%, exceeding the Culture Amp benchmark by three percentage points and placing us in the top quartile of nearly 2,000 companies in the Engagement and Inclusion benchmark. Standout results included employees noting high team effectiveness (90%) and growth and development (81%).

Inclusion and Culture

At Five9, we foster an inclusive environment by creating a culture where our employees can be their authentic selves. We endeavor to integrate our core values of honesty and respect in how we engage with one another, encourage leading with transparency and inclusivity and are committed to building a workplace culture where every employee feels they belong. Our goal is to empower our employees to have a voice that is heard and foster a community where they feel they belong. In our recruiting, we seek candidates from a wide array of sources to enable us to access the best candidates and build a broad base of skill sets and experience.

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Women represented 32% of our worldwide employees and racial and ethnic minorities represented 36% of our U.S. employees as of December 31, 2025. Women and ethnic minorities each represented 13% and 38%, respectively, of our executive leadership team and 30% and 50%, respectively, of our Board of Directors, or Board, as of December 31, 2025.

Total Rewards Philosophy

Our total rewards philosophy is a comprehensive approach designed to enable us to attract, engage, and retain talent in our industry by offering a differentiated and competitive overall employee value proposition. We believe our employees are central to our performance and long-term success, and we seek to align our total rewards programs with our business strategy, operating priorities, and evolving workforce needs.

Central to our philosophy is the principle of equitable compensation. We strive to ensure that our rewards system is fair, consistent, and transparent. This approach fosters a sense of belonging and commitment among our workforce, driving engagement and productivity.

Our total rewards philosophy reflects our commitment to creating a supportive and empowering environment for our employees, where they can thrive professionally and personally. By investing in our people in this way, we not only enhance individual well-being but also drive organizational performance and stakeholder value.

Our total rewards system encompasses not just competitive cash compensation, but a holistic package that addresses the needs of our workforce. This includes healthcare benefits, mental health benefits to employees and their dependents, financial and physical well-being programs, parental leave, fertility programs, retirement plans, performance bonuses, equity awards, and work-life balance initiatives.

Our total rewards strategy is designed to be responsive to market conditions and evolving business needs. We regularly benchmark our offerings against prevailing industry practices to ensure we remain competitive and appealing as an employer. Additionally, we embrace a culture of continuous feedback, allowing us to adapt and refine our rewards as appropriate to support retention, motivation, and the execution of our business strategy.

Talent Development

Talent development is a core component of our talent strategy to be competitive in a dynamic global market. We invest in employee growth through a range of talent development programs designed to build critical skills and leadership capabilities. Our Leadership Principles guide Talent Acquisition, Learning and Development, and Performance Management practices, supporting the identification and development of leadership capabilities at all levels. Talent review processes focus on identifying high-performing and high-potential employees.

Learning is supported across the employee lifecycle through enhanced onboarding, semi-annual development conversations between employees and managers, and investments in anytime learning via a centralized, on-demand learning platform offering skill-based learning pathways. We also invest in leadership capabilities through our Elevate Leadership Development Program, which reinforces leadership expectations and consistent leadership practices.

Through these investments, we endeavor to support a skilled and high-performing workforce aligned to our long-term business objective

Workplace Practices and Policies

We are committed to providing a workplace free of harassment or discrimination based on race, color, religion, sex, sexual orientation, gender identity, national origin, disability, veteran status, caste or other legally protected characteristic. We are an equal opportunity employer committed to inclusion.

Environmental Sustainability

We are committed to reducing workplace-related resource consumption through our site selection, facilities design and energy procurement practices through our landlords, to ensure our corporate responsibility goals are achieved. We participate in building sustainability by occupying LEED certified and 5-Star NABERS Energy Rated multi-tenant buildings. Our corporate headquarters offers a transportation program in effort to reduce emissions. In addition, we have made strides in reducing energy consumption by upgrading our lighting system and installing motion sensors for lighting and convenience electrical outlets. To reduce waste, we use source compostable/recyclable kitchen products, centralized waste collection with an emphasis on recycling, established an E-waste program, implemented software tools to minimize printing waste and reduce equipment and toner purchases, and expanded our battery recycling program to include work-related and personal battery recycling.

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We are also committed to complying with California’s evolving climate legislation. This commitment includes reporting to Scope 1, 2, and 3 emissions within the mandated reporting periods.

Regulatory

The following summarizes important, but not all, federal, state and foreign regulations that could impact our operations. Federal and state regulations are subject to judicial review, administrative revision and statutory changes through legislation that could materially affect how we and others in this industry operate.

The Telecommunications Act of 1996 vests the Federal Communications Commission, or FCC, with jurisdiction over interstate telecommunications services, while preserving state and local jurisdiction over many aspects of these services. As a result, telecommunications services are regulated at both the federal and state levels in the United States.

Many of the services we provide are classified as a telecommunications service provider for federal regulatory purposes. Since our business is regulated by the FCC and some state public utility commissions, we are subject to existing or potential state and federal regulations relating to privacy, disability access, Enhanced 911 access, access to and porting of numbers, automatic number dialing, contributions to the federal Universal Service Fund and related funds, or USF, and other requirements. There is uncertainty on how other services that we provide may become subject to FCC or state public utilities commission regulations. If we do not comply with FCC rules and regulations, we could be subject to FCC enforcement actions, fines and possibly restrictions on our ability to operate or offer certain of our services. Any enforcement action by the FCC, which may be a public process, would hurt our reputation in the industry, possibly impair our ability to sell our services to customers and could harm our business and results of operations. The Federal Trade Commission, or FTC, also has jurisdiction over some of our business practices, including advertising, trade practices, privacy and telemarketing. If we do not comply with FTC rules and regulations, we could be subject to an FTC enforcement action, fines or restrictions on our business practices.

We must comply with numerous federal and state regulations, including:

•Telephone Consumer Protection Act of 1991, or TCPA, which regulates the use of automatic dialing equipment and pre-recorded messages to contact consumers, the Telemarketing Sales Rule and state telemarketing laws, which have similar obligations as to telemarketing activities;

•the TRACED Act and corresponding regulations from the FCC, which require carriers to authenticate incoming calls using the STIR/SHAKEN caller ID framework and correspondingly compels providers of telecommunications services to implement capabilities to certify as authentic the traffic they provide to those carriers and to block transmission of certain calls;

•CALEA, which requires telecommunications service providers to assist law enforcement in undertaking electronic surveillance;

•enhanced 911 rules, KARI’s Law and RAY BAUM’s Act, which, in certain circumstances, require telecommunications service providers to ensure their users can directly dial 911 emergency services and, if technically feasible, automatically convey dispatchable location information with the call;

•contributions to the USF, which requires that we pay a percentage of our revenues resulting from the provision of interstate and some international telecommunications services to support certain federal programs;

•payment of annual FCC regulatory fees based on our interstate and international revenues;

•The Communications and Video Accessibility Act and rules pertaining to access to our services by people with disabilities and contributions to the Telecommunications Relay Services fund;

•FCC rules regarding Customer Proprietary Network Information, or CPNI, which require that we implement adequate safeguards against unlawful access to CPNI, and limit disclosure of certain information received from customers as a result of a service provider/customer relationship without customer approval, subject to certain exceptions;

•Federal Trade Commission Act and rules promulgated thereunder, which generally relate to avoiding unfair and deceptive trade practices, our advertising, use and deployment of certain AI-based services, and privacy practices;

•The Health Information Portability and Accountability Act (or HIPAA) and rules promulgated thereunder, which generally relate to the privacy and security of certain health-related information; and

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•The California Consumer Privacy Act (or CCPA) and comprehensive state privacy laws in other U.S. states that require compliance with privacy frameworks and include disclosure and permission-related obligations with respect to our collection, processing, and disclosure of personal data.

In addition, we must make contributions and other payments on our usage-based fees to state and local governmental entities. The tax and fee structure for communications services such as ours is complex, ambiguous and subject to interpretation. If taxing and regulatory authorities enact new rules or regulations or expand their interpretations of existing rules and regulations, we could incur additional liabilities. The amount that we are required to pay under certain of these tax and regulatory structures also continues to increase as a percentage of our telecommunications revenues. The collection of additional taxes, fees or surcharges in the future could increase our prices or reduce our profit margins. Compliance with these regulations may also make us less competitive with those competitors who are not subject to, or choose not to comply with, these regulations. See Note 10 of the notes to the consolidated financial statements under ITEM 8 of this Form 10-K for a discussion of our potential liability related to USF matters.

As we expand internationally, we will be subject to laws and regulations in the countries in which we offer our services. Regulation of the solutions we provide outside the U.S. varies from country to country, is often unclear, and may be more onerous than those imposed on our services in the U.S. For example, in the European Union, the General Data Protection Regulation, or the GDPR, requires companies to meet new and extended requirements regarding the processing of personal data. Non-compliance with the GDPR can trigger steep fines of up to €20 million or 4% of total worldwide annual turnover, whichever is higher. In addition, among other comprehensive privacy laws around the world, we are subject to the UK’s Data Protection Act, and Canada’s Personal Information Protection and Electronic Documents Act, or PIPEDA, and analogous provincial laws. We also hold a Unified License Virtual Network Operator in India. This license requires us to comply with certain quality of service, privacy and billing standards associated with our services in India that may be different than the standards imposed by other countries. Our regulatory obligations in foreign jurisdictions could impact the use or cost of our solution in international locations as data protection and privacy laws and regulations around the world continue to evolve, and which may also address the use of certain types of AI-based systems and solutions within their scope, including the EU Artificial Intelligence Act.

Furthermore, we have defined and implemented a layered information governance program comprising a defined framework of policies, operational processes and controls. Our framework was developed using international, sector or "data type" specific standards including, but not limited to:

•International Organization for Standardization - ISO 27001:2013 Information Security Management Systems Standard;

•Payment Card Industry Data Security Standard. PCI DSS 3.2;

•AICPA - System and Organization Controls SOC 2, Type 2 Security and Availability criteria;

•ISO 27017 - Information technology – Security techniques – Code of practice for information security controls based on ISO/IEC 27002 for cloud services;

•ISO 27018 - Information technology — Security techniques — Code of practice for protection of personally identifiable information (PII) in public clouds acting as PII processors; and

•NIST 800-53 Rev 5 - Security and Privacy Controls for Information Systems and Organizations.

A key component of our framework is that it evolves based on the changing needs of our business, customer and regulatory framework requirements. Additionally, our framework is subject to annual independent verification audits performed by qualified and experienced external third parties who issue to us SOC 2 Type 2, PCI AOC, and HIPAA HiTech attestation reports, and who certify us to the ISO 27001:2013 Information Security Management System standard.

The legislative and regulatory scheme, as well as the information governance programs, relevant to telecommunications service providers and other solutions we provide will continue to evolve and can be expected to change the competitive environment for these services. It is not possible to predict how such evolution and changes will affect our business or our industry. If we do not comply with current or future rules or regulations that apply to our business, we could be subject to substantial fines and penalties, we may have to restructure our service offerings, exit certain markets, accept lower margins or raise the price of our services, any of which could harm our business

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and results of operations. See “Risk Factors — Risks Related to Regulatory Matters” under ITEM 1A of this Form 10-K for more information.

Company Information

We were incorporated in Delaware in 2001. We operate in a single reportable segment. Our principal executive office is located at 3001 Bishop Drive, Suite 350, San Ramon, CA 94583 and our telephone number is (925) 201-2000. Our website address is www.five9.com. Our website and the information contained therein or connected thereto shall not be deemed to be incorporated into this annual report on Form 10-K. We own or have rights to trademarks or trade names that we use in connection with the operation of our business, including our corporate names, logos and domain names. In addition, we own or have the rights to copyrights, trade secrets and other proprietary rights that protect the content of our solution. Solely for convenience, some of the copyrights, trademarks and trade names referred to in this annual report on Form 10-K are listed without ©, ® and ™ symbols, but we own and will assert, to the fullest extent under applicable law, our rights to our copyrights, trademarks and trade names.

Available Information

Our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, proxy and information statements and amendments to reports are filed with, or furnished to, the United States Securities and Exchange Commission, or SEC, pursuant to the Securities Exchange Act of 1934, as amended, or the Exchange Act. The SEC maintains a website at https://www.sec.gov that contains reports, proxy and information statements and other information regarding Five9 and other companies that file materials with the SEC electronically. Copies of our reports on Form 10-K, Forms 10-Q and Forms 8-K, and amendments thereto, may be obtained, free of charge, electronically through our internet website, http://investors.five9.com/sec.cfm as soon as reasonably practicable after such material is filed electronically with, or furnished to, the SEC. The information on our website is not a part of, or incorporated by reference into, this Annual Report on Form 10-K.