Exhibit 99.1

SAN JOSE, California, July 28, 2025 - Harmonic Inc. (NASDAQ: HLIT) today announced its unaudited results for the second quarter of 2025.

“Our team delivered strong second quarter results with revenue and profitability in both our Video and Broadband businesses exceeding the high end of our guidance,” said Nimrod Ben-Natan, president and chief executive officer of Harmonic. “We are seeing further momentum in Video and while we expect Broadband upgrade activity to persist at a moderate pace in 2025, we are beginning to see positive indicators, with improving customer ramp readiness and progress on Unified DOCSIS 4.0, which we expect will turn into tailwinds for us in 2026.”

Q2 Financial and Business Highlights

•Revenue: $138.0 million, compared to $138.7 million in the prior year period

◦Broadband segment revenue: $86.9 million, compared to $92.9 million in the prior year period

◦Video segment revenue: $51.1 million, compared to $45.8 million in the prior year period

•Gross margin: GAAP 53.5% and Non-GAAP 54.1%, both higher compared to GAAP 52.9% and Non-GAAP 53.1% in the prior year period

◦Broadband segment Non-GAAP gross margin: 46.5% compared to 47.6% in the prior year period

◦Video segment Non-GAAP gross margin: 67.0% compared to 64.4% in the prior year period

•Operating income (loss): GAAP income $3.9 million and Non-GAAP income $13.9 million, compared to GAAP loss $15.6 million and Non-GAAP income $12.2 million in the prior year period

•Net income (loss): GAAP net income $2.9 million and Non-GAAP net income of $10.3 million, compared to GAAP net loss $12.5 million and Non-GAAP net income $9.3 million in the prior year period

•Non-GAAP adjusted EBITDA: $17.0 million compared to $16.1 million in the prior year period

•Net income (loss) per share: GAAP net income per share of $0.03 and Non-GAAP net income per share of $0.09, compared to GAAP net loss per share of $0.11 and Non-GAAP net income per share of $0.08 in the prior year period

•Backlog and deferred revenue of $504.5 million

•Cash: $123.9 million, compared to $45.9 million in the prior year period

•Repurchased approximately 1.6 million shares of common stock for an aggregate amount of $14.0 million

•Commercially deployed our cOSTM solution with 136 customers, serving 35.3 million cable modems

•Won four new broadband customers including two fiber customers

•Announced the introduction of SeaStarTM Optical Node, which redefines broadband connectivity for low density multiple dwelling units

•Recently announced a record-breaking DOCSIS 4.0 demonstration of 14 Gbps downstream across a multi-vendor network at the CableLabs® Interop event

•Record Video SaaS revenue of $15.4 million in Q2 reflects continued growth, especially in sports streaming

(1) Adjusted EBITDA is a Non-GAAP financial measure. Refer to "Preliminary Net Income (Loss) to Consolidated Segment Adjusted EBITDA Reconciliation" below for a reconciliation to net income (loss), the most comparable GAAP measure.

* Not applicable

Explanations regarding our use of Non-GAAP financial measures and related definitions, and reconciliations of our GAAP and Non-GAAP measures, are provided in the sections below entitled “Use of Non-GAAP Financial Measures” and “GAAP to Non-GAAP Reconciliations.”

(1) Includes estimated tariff impacts of approximately $1 million

(2) Diluted shares assumes stock price at $9.13 (Q2 2025 average price).

(1) Refer to “Use of Non-GAAP Financial Measures” and “GAAP to Non-GAAP Reconciliations on Financial Guidance” below. Components may not sum to total due to rounding.

(2) Includes estimated tariff impacts of approximately $1 million

(3) Refer to “Net Income (Loss) to Consolidated Adjusted EBITDA Reconciliation on Financial Guidance” below for a reconciliation to net income (loss), the most comparable GAAP measure.

(4) Diluted shares assumes stock price at $9.13 (Q2 2025 average price).

Harmonic will host a conference call to discuss its financial results at 2:00 p.m. PT (5:00 p.m. ET) on Monday, July 28, 2025. The live webcast will be available on the Harmonic Investor Relations website at http://investor.harmonicinc.com. To participate via telephone, please register in advance using this link, https://register-conf.media-server.com/register/BIb056948f450247ab97d84d9326ae54f8. A replay will be available after 5:00 p.m. PT on the same website.

Harmonic (NASDAQ: HLIT), the worldwide leader in virtualized broadband and video delivery solutions, enables media companies and service providers to deliver ultra-high-quality video streaming and broadcast services to consumers globally. The company revolutionized broadband networking via the industry’s first virtualized broadband solution, enabling operators to more flexibly deploy gigabit internet service to consumers’ homes and mobile devices. Whether simplifying OTT video delivery via innovative cloud and software platforms, or powering the delivery of gigabit internet services, Harmonic is changing the way media companies and service providers monetize live and on-demand content on every screen. More information is available at www.harmonicinc.com.

This press release 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, including statements related to anticipated customer purchases and deployments of our Unified DOCSIS 4.0 solutions and our expectations regarding: net revenue, gross margins, operating expenses, operating income (loss), Adjusted EBITDA, tax expense and tax rate, and net income (loss) per diluted share. Our expectations regarding these matters may not materialize, and actual results in future periods are subject to risks and uncertainties that could cause actual results to differ materially from those projected. These risks include, in no particular order, the following: customer concentration and consolidation; loss of one or more key customers; delays or decreases in capital spending in the cable, satellite telco, broadcast and media industries; the possibility that our products will not generate sales that are commensurate with our expectations or that our cost of revenue or operating expenses may exceed our expectations; the market and technology trends underlying our Broadband and Video businesses will not continue to develop in their current direction or pace; the impact of tariffs and general economic conditions on our sales and operations; the mix of products and services sold in various geographies and the effect it has on gross margins; our ability to develop new and enhanced products in a timely manner and market acceptance of our new or existing products; risks associated with our international operations; exchange rate fluctuations of the currencies in which we conduct business; risks associated with our cOSTM and VOS product solutions; dependence on various broadband and video industry trends; inventory management; the lack of timely availability or the impact of increases in the prices of parts or raw materials necessary to produce our products; the effect of competition, on both revenue and gross margins; difficulties associated with rapid technological changes in our markets; risks associated with unpredictable sales cycles; our dependence on contract manufacturers and sole or limited source suppliers; stock repurchases may not be conducted in the timeframe or in the manner we expect, or at all; and the impact on our business of natural disasters. The forward-looking statements contained in this press release are also subject to other risks and uncertainties, including those more fully described in Harmonic's filings with the Securities and Exchange Commission, including our most recent Annual Report on Form 10-K for the year ended December 31, 2024, our most recent Quarterly Report on Form 10-Q and our Current Reports on Form 8-K. The forward-looking statements in this press release are based on information available to the Company as of the date hereof, and Harmonic disclaims any obligation to update any forward-looking statements.

The Company reports its financial results in accordance with accounting principles generally accepted in the United States (“GAAP” or referred to herein as “reported”). However, management believes that certain Non-GAAP financial measures provide management and other users with additional meaningful financial information that should be considered when assessing our ongoing performance. Our management regularly uses our supplemental Non-GAAP financial measures internally to understand, manage and evaluate our business, establish operating budgets, set internal measurement targets and make operating decisions.

These Non-GAAP measures are not in accordance with, or an alternative for, measures prepared in accordance with generally accepted accounting principles and may be different from Non-GAAP measures used by other companies. In addition, these Non-GAAP measures are not based on any comprehensive set of accounting rules or principles. The Company believes that Non-GAAP measures have limitations in that they do not reflect all of the amounts associated with Harmonic's results of operations as determined in accordance with GAAP and that these measures should only be used to evaluate Harmonic's results of operations in conjunction with the corresponding GAAP measures.

The Company believes that the presentation of Non-GAAP measures, when shown in conjunction with the corresponding GAAP measures, provides useful information to investors and management regarding financial and business trends relating to its financial condition and its historical and projected results of operations. Non-GAAP financial measures should be viewed in addition to, and not as an alternative to, the Company’s reported results prepared in accordance with GAAP.

The Non-GAAP measures presented here are: Gross profit, operating expenses, income (loss) from operations, non-operating expenses and net income (loss), Adjusted EBITDA (including those amounts as a percentage of revenue) and net income (loss) per diluted share. The presentation of Non-GAAP information is not intended to be considered in isolation or as a substitute for results prepared in accordance with GAAP, and is not necessarily comparable to Non-GAAP results published by other companies. A reconciliation of the historical Non-GAAP financial measures discussed in this press release to the most directly comparable historical GAAP financial measures is included with the financial statements provided with this press release. The Non-GAAP adjustments described below have historically been excluded from our GAAP financial measures.

Our Non-GAAP financial measures reflect adjustments based on the following items, as well as the related income tax effects:

Stock-based compensation - Although stock-based compensation is a key incentive offered to our employees, we continue to evaluate our business performance excluding stock-based compensation expenses. We believe that management is limited in its ability to project the impact stock-based compensation would have on our operating results. In addition, for comparability purposes, we believe it is useful to provide a Non-GAAP financial measure that excludes stock-based compensation in order to better understand the long-term performance of our core business and to facilitate the comparison of our results to the results of our peer companies.

Restructuring and related charges - Harmonic from time to time incurs restructuring charges which primarily consist of employee severance, one-time termination benefits related to the reduction of its workforce, and other costs. These charges are associated with material business shifts. We exclude these items because we do not believe they are reflective of our ongoing long-term business and operating results.

Non-cash interest expense related to convertible notes - We record the amortization of issuance costs as non-cash interest expense. We believe that excluding these costs provides meaningful supplemental information regarding operational performance and liquidity, along with enhancing investors’ ability to view the Company’s results from management’s perspective. In addition, we believe excluding these costs from the Non-GAAP measures facilitates comparisons to our historical operating results and comparisons to peer company operating results.

Depreciation - Depreciation expense is excluded from Adjusted EBITDA as this is a non-cash item unrelated to the ordinary course of our business and not reflective of our underlying business performance.

Non-recurring advisory fees - There were non-recurring costs that we excluded from Non-GAAP results relating to professional accounting, tax and legal fees associated with strategic corporate initiatives.

Asset impairment and related charges - We exclude asset impairment and related charges due to the nature of such expenses being unusual and arising outside the ordinary course of continuing operations. These costs primarily consist of impairments of fixed assets, right-of-use assets and related leasehold improvements, and other unrecoverable facility costs due to the intended change in use of certain leased space.

Discrete tax items and tax effect of Non-GAAP adjustments - The income tax effect of Non-GAAP adjustments relates to the tax effect of the adjustments that we incorporate into Non-GAAP financial measures in order to provide a more meaningful measure of Non-GAAP net income.

(1) Segment gross margin and segment gross profit are Non-GAAP financial measures. Refer to “Use of Non-GAAP Financial Measures” above and “GAAP to Non-GAAP Reconciliations" below.

(1) Includes impairment charges of $2.9 million for right-of-use assets, $4.2 million for leasehold improvements, and $1.9 million related to the fair value of other

unrecoverable facility costs.

(1) Includes impairment charges of $2.9 million for right-of-use assets, $4.2 million for leasehold improvements, and $1.9 million related to the fair value of other unrecoverable facility costs.

(1) Adjusted EBITDA and Adjusted EBITDA margin are Non-GAAP financial measures. Refer below for the "Net Income (Loss) to Consolidated Segment Adjusted EBITDA Reconciliation."

Calculation of Adjusted EBITDA by Segment on Financial Guidance (Unaudited) (1)

(2) Segment Adjusted EBITDA is a Non-GAAP financial measure. Refer below for the "Net Income (Loss) to Consolidated Segment Adjusted EBITDA reconciliation on Financial Guidance." Net Income (Loss) to Consolidated Segment Adjusted EBITDA Reconciliation on Financial Guidance (Unaudited) (1)