Participants should plan to dial in or log on ten minutes prior to the start time. A telephonic replay of the call will be available until November 19, 2018. The webcast will be archived on 8x8's website for a period of 30 days. For additional information, visit http://investors.8x8.com.

8x8, Inc. (NYSE:EGHT) cloud solutions help businesses transform their customer and employee experience. With one system of engagement for cloud voice, video, collaboration and contact center and one system of intelligence on one technology platform, businesses can now communicate faster and smarter to exceed the speed of customer expectations. For additional information, visit www.8x8.com, or follow 8x8 on LinkedIn, Twitter, and Facebook.

The Company has provided in this release financial information that has not been prepared in accordance with Generally Accepted Accounting Principles (GAAP). Management uses these non-GAAP financial measures internally in analyzing the Company's financial results and believes they are useful to investors, as a supplement to GAAP measures, in evaluating the Company's ongoing operational performance. Management believes that the use of these non-GAAP financial measures provides an additional tool for investors to use in evaluating 8x8's ongoing operating results and trends and in comparing financial results with other companies in the industry, many of which present similar non-GAAP financial measures to investors.

The Company has defined non-GAAP net income (loss) as net income (loss) under GAAP, plus amortization of acquired intangible assets, impairment charges, stock-based compensation, certain other income and expenses, and the provision for or benefit from income taxes. Amortization of acquired intangible assets are excluded because it is a non-cash expense that management does not consider part of ongoing operations when assessing the Company's financial performance. Stock-based compensation expense has been excluded because it is a non-cash expense and relies on valuations based on future conditions and events, such as the market price of 8x8 common stock, that are difficult to predict and/or largely not within the control of management. Certain other income and expense items, such as acquisition-related, certain severance expenses and expenses for tax or litigation risks, have been excluded because management considers them one-time events or otherwise not indicative of trends in the Company's ongoing operations. The Company has also excluded non-cash rent expense related to its new headquarter building because the building remains in the built-out phase.

GAAP tax provision (benefit) for income taxes has been excluded as management does not consider taxes in its analysis of the performance of ongoing operations. Due to the Company's history of tax losses and full valuation allowance against deferred tax assets, future GAAP and Non-GAAP effective tax rates are limited to current taxes in certain US state and foreign jurisdictions. The Company reports these current taxes as reduction from Non-GAAP pretax net income to derive Non-GAAP net income after taxes.

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The Company defines non-GAAP net income (loss) per share as non-GAAP net income (loss) divided by the weighted-average basic or diluted shares outstanding which includes the effect of potentially dilutive stock options and awards.

Management believes that such exclusions facilitate comparisons to the Company's historical operating results and to the results of other companies in the same industry, and provides investors with information that management uses in evaluating the Company's performance on a quarterly and annual basis.

Although these non-GAAP financial measures adjust expenses, they should not be viewed as a pro forma presentation reflecting the elimination of the underlying share- based compensation programs, which are an important element of the Company's compensation structure. GAAP requires that all forms of share-based payments should be valued and included in the results of operations.

In addition, this release includes financial measures that have been adjusted as follows:

• This release includes revenue figures adjusted to exclude revenue generated by DXI. As first reported in the third quarter of our 2018 fiscal year, we have de- emphasized the sale of DXI's ContactNow as a stand-alone product, and management therefore believes it is useful to exclude this revenue from period-to-period comparisons to better depict the relative performance of our core business.

• This release includes revenue figures adjusted for comparison on a constant currency basis, when management concluded that the elimination of the impact of currency fluctuations between the periods being compared would assist with the evaluation of the underlying business performance.

We disclose these non-GAAP financial measures to the public as an additional means by which investors can assess our performance. These non-GAAP financial measures may be calculated differently from, and therefore may not be comparable to, similarly titled measures used by other companies. Non-GAAP financial measures should not be considered in isolation from, or as a substitute for, financial information prepared in accordance with GAAP. Investors are encouraged to review the reconciliation of these non-GAAP financial measures to their most directly comparable GAAP financial measures. This reconciliation has been provided in the financial statement tables included below in this press release.

Forward Looking Statements:

This news release contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 and Section 21E of the Securities Exchange Act of 1934. These statements include, without limitation, information about future events based on current expectations, potential product development efforts, near and long-term objectives, potential new business, strategies, organization changes, changing markets, future business performance and outlook. Such statements are predictions only, and actual events or results could differ materially from those made in any forward-looking statements due to a number of risks and uncertainties. Actual results and trends may differ materially from historical results or those projected in any such forward-looking statements depending on a variety of factors.

These factors include, but are not limited to:

• customer acceptance and demand for our cloud communication and collaboration services,
• changes in the competitive dynamics of the markets in which we compete,
• the quality and reliability of our services,
• customer cancellations and rate of churn,
• our ability to scale our business,
• customer acquisition costs,
• our reliance on infrastructure of third-party network services providers,

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• risk of failure in our physical infrastructure,
• risk of failure of our software,
• our ability to maintain the compatibility of our software with third-party applications and mobile platforms,
• continued compliance with industry standards and regulatory requirements in the United States and foreign countries in which we make our software solutions available, and the costs of such compliance,
• the risk that our actual liability for state and municipal taxes, fees and surcharges may exceed our accrued contingent liability for these amounts,
• risks relating to our strategies and objectives for future operations, including the execution of integration plans and realization of the expected benefits of our acquisitions,
• the amount and timing of costs associated with recruiting, training and integrating new employees,
• timing and extent of improvements in operating results from increased spending in marketing, sales, and research and development,
• introduction and adoption of our cloud software solutions in markets outside of the United States,
• risk of cybersecurity breaches and other unauthorized disclosures of personal data,
• general economic conditions that could adversely affect our business and operating results,
• implementation and effects of new accounting standards and policies in our reported financial results, and
• potential future intellectual property infringement claims and other litigation that could adversely affect our business and operating results.

For a discussion of such risks and uncertainties, which could cause actual results to differ from those contained in the forward-looking statements, see "Risk Factors" in the Company's reports on Forms 10-K and 10-Q, as well as other reports that 8x8, Inc. files from time to time with the Securities and Exchange Commission. All forward-looking statements are qualified in their entirety by this cautionary statement, and 8x8, Inc. undertakes no obligation to update publicly any forward-looking statement for any reason, except as required by law, even as new information becomes available or other events occur in the future.

8x8, Inc.

Investor Relations:
Victoria Hyde-Dunn
1-669-333-5200

or

Media:
John Sun
1-408-692-7054
john.sun@@8x8.com

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8x8, Inc.
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
(In thousands, except per share amounts; unaudited)