Five9, Inc.

We calculate non-GAAP net income by adding back or removing the following items to or from GAAP net loss stock-based compensation, intangibles amortization, amortization of discount and issuance costs on convertible senior notes, gain on early extinguishment of debt, exit costs related to the closure and relocation of our Russian operations, acquisition and related transaction costs and one-time integration costs, costs related to a reduction in force plan, one-time expenses related to strategic consulting services for operational review, other cost-reduction and productivity initiatives, legal fees related to the securities class action, and office closure lease termination costs.

SEC original ↗Five9, Inc. — Earnings release (8-K exhibit)EX-99Jul 31, 2025

In November 2024, the FASB issued ASU 2024-04, Debt with Conversion and Other Options (Subtopic 470-20) , which clarifies the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

agency and government-sponsored securities ( 471 ) 136,110 ( 14 ) 33,935 Commercial paper ( 9 ) 7,541 Municipal bonds ( 2 ) 1,226 Corporate bonds ( 112 ) 21,626 Total $ ( 929 ) $ 348,271 $ ( 14 ) $ 33,935 Although the Company had certain available-for-sale debt securities in an unrealized loss position as of June 30, 2026, no impairment loss was recorded since it did not intend to sell them, did not anticipate a need to sell them, and the decline in fair value was not due to any credit-related factors.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

agency and government-sponsored securities 166,237 166,237 Commercial paper 7,873 7,873 Corporate bonds 22,528 22,528 Total marketable investments $ 267,130 $ 197,705 $ $ 464,835 In March 2024, the Company issued $ 747.5 million aggregate principal amount of 1.00 % convertible senior notes due 2029 (the "2029 convertible senior notes") in a private offering.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

In connection with the issuance of the 2029 convertible senior notes, the Company used part of the net proceeds from the issuance to repurchase approximately $ 313.1 million aggregate principal amount of its 0.50 % convertible senior notes due 2025 (the "2025 convertible senior notes").

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

Debt 2029 Convertible Senior Notes and Related Capped Call Transactions In March 2024, the Company issued $ 747.5 million aggregate principal amount of 2029 convertible senior notes in a private offering, which aggregate principal amount included the exercise in full of the initial purchasers option to purchase up to an additional $ 97.5 million principal amount of the 2029 convertible senior notes.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

Since stepping into the interim CFO role earlier this year, he has helped us execute on our operational and financial goals, including the implementation of strategic initiatives to drive increased profitability and top line growth.

SEC original ↗Five9, Inc. — Earnings release (8-K exhibit)EX-99Jul 31, 2025

We calculate non-GAAP operating income by adding back or removing the following items to or from GAAP loss from operations stock-based compensation, intangibles amortization, exit costs related to the closure and relocation of our Russian operations, acquisition related transaction costs and one-time integration costs, costs related to a reduction in force plan, one-time expenses related to strategic consulting services for operational review, other cost-reduction and productivity initiatives, legal fees related to the securities class action, and office closure lease termination costs.

SEC original ↗Five9, Inc. — Earnings release (8-K exhibit)EX-99Jul 31, 2025

We calculate non-GAAP net income by adding back or removing the following items to or from GAAP net loss stock-based compensation, intangibles amortization, amortization of discount and issuance costs on convertible senior notes, gain on early extinguishment of debt, exit costs related to the closure and relocation of our Russian operations, acquisition and related transaction costs and one-time integration costs, costs related to a reduction in force plan, one-time expenses related to strategic consulting services for operational review, other cost-reduction and productivity initiatives, legal fees related to the securities class action, and office closure lease termination costs.

SEC original ↗Five9, Inc. — Earnings release (8-K exhibit)EX-99Jul 31, 2025

These statements reflect the current views of our senior management with respect to future events, strategies and financial trends and performance.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

These forward-looking statements include statements with respect to our business, expenses, strategies, losses, growth plans, product and customer initiatives, market growth projections, and our industry, including those set forth under Management s Discussion and Analysis of Financial Condition and Results of Operations and elsewhere in this Quarterly Report.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

Five9 emphasizes that the guidance is subject to various important cautionary factors referenced in the section entitled Forward-Looking Statements below, including risks and uncertainties associated with the ongoing impact of macroeconomic challenges.

SEC original ↗Five9, Inc. — Earnings release (8-K exhibit)EX-99Jul 31, 2025

Legal Proceedings 47 ITEM 1A.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

Exhibits 50 SIGNATURES 51 1 Table of Contents SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, which involve substantial risks and uncertainties.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

Forward-looking statements address matters that involve risks and uncertainties.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

If one or more of these or other risks or uncertainties materialize, or if our underlying assumptions prove to be incorrect, our actual results may differ materially from what we anticipate.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026

Any forward-looking statements you read in this report reflect our views only as of the date of this report with respect to future events and are subject to these and other risks, uncertainties and assumptions relating to our operations, results of operations, growth strategy and liquidity.

SEC original ↗Five9, Inc. — 10-Q Quarterly report10-QAug 6, 2026