Exhibit 99.1

Media Contact

Tabitha Long

(312) 384-8018

FOR IMMEDIATE RELEASE

Inteliquent Reports Preliminary Second Quarter 2013 Results and Postpones Earnings Call

CHICAGO, August 8, 2013 – Inteliquent, Inc. (Nasdaq: IQNT), a leading provider of voice services, today announced preliminary financial results for the second quarter of 2013. Inteliquent also announced that, as a result of an ongoing investigation by the Audit Committee of Inteliquent’s Board of Directors, it has postponed its scheduled earnings call, which had been set for Thursday, August 8, 2013.

Preliminary Financial Results for the Second Quarter of 2013 and 2013 Financial Estimates

Inteliquent generated revenue of $49.8 million in the second quarter of 2012. Adjusted EBITDA (a non-GAAP financial measure) in the second quarter of 2013 was $16.3 million. See “Use of Non-GAAP Financial Measures” below for a discussion of the presentation of Adjusted EBITDA and reconciliation to net income. Inteliquent also affirmed its financial estimates for 2013 as more fully described below.

Postponed Earnings Call

As previously disclosed in its Annual Report on Form 10-K for the year ended December 31, 2012, Inteliquent reported a $75.3 million impairment charge, and a net loss of $78.1 million, in each case for the year ended December 31, 2012.

During the second quarter of 2013, the Board of Directors of the Company determined that an internal investigation of whether such impairment charge was overstated should be undertaken by the Audit Committee with the assistance of independent outside professionals. During the same time period, the Board of Directors also determined that the Audit Committee, with the assistance of independent outside professionals, should conduct an internal investigation of the Company’s financial forecasting practices during the fourth quarter of 2012 and the first quarter of 2013. As a result of the ongoing internal investigation, Inteliquent has postponed its scheduled second quarter earnings call, which had been set for Thursday, August 8, 2013 at 10:00 a.m. Eastern time.

The information contained in this press release is preliminary and may be subject to significant changes and adjustments as a result of the Audit Committee’s ongoing internal investigation. Inteliquent is still conducting its internal investigation, including investigating whether a restatement of its financial statements relating to an overstatement of the impairment charge for the year ended December 31, 2012 will be required. All results reflected in this press release should be considered preliminary until Inteliquent’s Quarterly Report on Form 10-Q for the second quarter ended June 30, 2013 is filed with the Securities and Exchange Commission.

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Preliminary Second Quarter Highlights

($ in millions, except per minute figures)

Preliminary Financial and Operating Results

In the second quarter of 2013, Inteliquent generated voice revenue of $49.8 million, a decrease of 2% compared to $50.8 million of voice revenue in the second quarter of 2012. The decrease related primarily to a reduction in minute volumes for local transit and termination voice services, which was partially offset by an increase in volumes in our origination voice services. Revenue from continuing operations for the second quarter of 2013 and 2012 included $2.7 million and $6.7 million, respectively, related to the global data business sold on April 30, 2013.

Voice minutes of use decreased by 10% to 29.4 billion minutes in the second quarter of 2013, compared to 32.8 billion minutes in the second quarter of 2012. Voice average price per minute increased by 9% over the same time period.

Adjusted EBITDA (a non-GAAP financial measure) in the second quarter of 2013 was $16.3 million, a decrease of 12% from $18.5 million in the second quarter of 2012. See “Use of Non-GAAP Financial Measures” below for a discussion of the presentation of Adjusted EBITDA and reconciliation to net income.

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Income from continuing operations in the second quarter of 2013 was $35.2 million, compared to $10.7 million in the second quarter of 2012. The increase in the second quarter of 2013 related primarily to a $24.0 million gain on sale of part of the global data business.

Discontinued Operations

On April 30, 2013, we completed the divesture of the global data business businesses, allowing us to focus resources on driving performance in the core voice business. In the second quarter of 2013, our net loss from discontinued operations was $1.7 million, which compared to a $7.0 million net loss from discontinued operations in the second quarter of 2012. In addition we recorded $1.0 million of gain in connection with the sale of our global data business that qualified for discontinued operations treatment.

Dividends and Share Repurchases

We paid a $1.25 per share special dividend and initiated a $0.0625 per share regular quarterly dividend during the second quarter. This represented our first regular dividend since becoming a public company in 2007. Including the $3.00 per share special dividend that we paid on October 30, 2012, we have paid over $4.30 per share in dividends to our shareholders in the last 9 months. During the second quarter, we also repurchased 268,364 shares for approximately $1.57 million. The repurchases represented our initial activity under the three-year, $50 million program approved by the Board of Directors in August 2012.

2013 Business Outlook

As previously announced, we increased our financial estimates for 2013 as follows:

The financial estimates include the results for our global data business prior to its divestiture on April 30, 2013.

Cautionary Statement Regarding Forward-Looking Statements

This press release contains “forward-looking statements” that involve substantial risks and uncertainties. The information contained in this press release is preliminary and may be subject to significant changes and adjustments as a result of the Audit Committee’s ongoing internal investigation. Inteliquent is still investigating whether a restatement of its financial statements relating to its impairment charge will be required. All results reflected in this press release should be considered preliminary until Inteliquent’s Quarterly Report on Form 10-Q for the second quarter ended June 30, 2013 is filed with the Securities and Exchange Commission.

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In addition, the words “preliminary,” “anticipates,” “believes,” “efforts,” “expects,” “estimates,” “projects,” “proposed,” “plans,” “intends,” “may,” “will,” “would,” and similar expressions identify additional forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. Factors that might cause such differences include, but are not limited to: the results of the Audit Committee’s ongoing internal investigation, including the impact of any restatement of Inteliquent’s financial statements, if a restatement is required, or other actions that may be taken or required as a result of the Audit Committee’s ongoing internal investigation; the impact of any determination that certain of Inteliquent’s financial statements were not prepared in accordance with GAAP and/or the reporting requirements of applicable securities laws, rules and regulations; the impact of any determination of the existence of any significant deficiencies and/or material weaknesses in certain of Inteliquent’s internal controls and/or of the need to reevaluate certain of the findings and conclusions in Management’s Report on Internal Controls and/or any determination that Inteliquent’s disclosure controls and procedures required by the Securities Exchange Act were not effective; the impact of any inability of Inteliquent to timely file reports or statements with the Securities and Exchange Commission and distribute such reports or statements to its stockholders; the impact of the Audit Committee’s ongoing internal investigation on Inteliquent’s insurance policies and any determination as to whether Inteliquent is in compliance with the terms and conditions of such policies; any litigation and governmental investigations or proceedings which may arise out of the Audit Committee’s ongoing internal investigation or any restatement of Inteliquent’s financial statements; any impact of the Audit Committee’s ongoing internal investigation on Inteliquent’s borrowing capability and existing credit facility; any impact of the Audit Committee’s ongoing internal investigation on Inteliquent’s ability to meet NASDAQ requirements for continued listing; any impact of any tax consequences of the Audit Committee’s ongoing internal investigation, including any determination that Inteliquent filed tax returns were not true, correct and complete; the costs related to any litigation and governmental investigations or proceedings which may arise out of the Audit Committee’s ongoing internal investigation; the effects of competition, including direct connects, and downward pricing pressure resulting from such competition; risks associated with the sale of our data business, including issues regarding separating our network, IT and billing systems from the network and systems sold to the buyer, and that the cost savings and other benefits we hope to receive may not materialize in part or at all; our ability to maintain relationships with business providers following the sale of the data business; our regular review of strategic alternatives; the impact of current and future regulation, including intercarrier compensation reform enacted by the Federal Communications Commission; the risks associated with our ability to successfully develop and market new services, many of which are beyond our control and all of which could delay or negatively affect our ability to offer or market new services; technological developments; the ability to obtain and protect intellectual property rights; the impact of current or future litigation; the potential impact of any future acquisitions, mergers or divestitures; natural or man-made disasters; the ability to attract, develop and retain executives and other qualified employees; changes in general economic or market conditions; and other important factors included in our reports filed with the Securities and Exchange Commission, particularly in the “Risk Factors” section in our Annual Report on Form 10-K for the period ended December 31, 2012, as such Risk Factors may be updated from time to time in subsequent reports.

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Furthermore, such forward-looking statements speak only as of the date of this press release. We undertake no obligation to update any forward-looking statements to reflect events or circumstances after the date of such statements.

About Inteliquent

Inteliquent is a leading provider of wholesale voice services for carriers and service providers. Inteliquent is used by nearly all national and regional wireless carriers, cable companies and CLECs in the markets it serves, and its network carries approximately ten billion minutes of traffic per month. Please visit Inteliquent’s website at www.inteliquent.com and follow us on Twitter @Inteliquent.

The condensed consolidated statements of income, balance sheets and statements of cash flows are unaudited and subject to reclassification.

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INTELIQUENT, INC. AND SUBSIDIARIES

PRELIMINARY CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(Unaudited)

The information contained in this press release is preliminary and may be subject to significant changes and adjustments as a result of the Audit Committee’s ongoing internal investigation. Inteliquent is still investigating whether a restatement of its financial statements relating to its 2012 impairment charge could be required. To the extent Inteliquent’s $75.3 million impairment charge recognized for the year ended December 31, 2012, was overstated, a reduction of such charge would, among other matters, increase net income and impact additional financial statement accounts including the gain recognized by Inteliquent on the sale of its data business completed April 30, 2013. All results reflected in this press release should be considered preliminary until Inteliquent’s Quarterly Report on Form 10-Q for the second quarter ended June 30, 2013 is filed with the Securities and Exchange Commission.

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INTELIQUENT, INC. AND SUBSIDIARIES

PRELIMINARY CONDENSED CONSOLIDATED BALANCE SHEETS

(Unaudited)

The information contained in this press release is preliminary and may be subject to significant changes and adjustments as a result of the Audit Committee’s ongoing internal investigation. Inteliquent is still investigating whether a restatement of its financial statements relating to its 2012 impairment charge could be required. To the extent Inteliquent’s $75.3 million impairment charge recognized for the year ended December 31, 2012, was overstated, a reduction of such charge would, among other matters, increase net income and impact additional financial statement accounts including the gain recognized by Inteliquent on the sale of its data business completed April 30, 2013. All results reflected in this press release should be considered preliminary until Inteliquent’s Quarterly Report on Form 10-Q for the second quarter ended June 30, 2013 is filed with the Securities and Exchange Commission.

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INTELIQUENT, INC. AND SUBSIDIARIES

PRELIMINARY CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

The information contained in this press release is preliminary and may be subject to significant changes and adjustments as a result of the Audit Committee’s ongoing internal investigation. Inteliquent is still investigating whether a restatement of its financial statements relating to its 2012 impairment charge could be required. To the extent Inteliquent’s $75.3 million impairment charge recognized for the year ended December 31, 2012, was overstated, a reduction of such charge would, among other matters, increase net income and impact additional financial statement accounts including the gain recognized by Inteliquent on the sale of its data business completed April 30, 2013. All results reflected in this press release should be considered preliminary until Inteliquent’s Quarterly Report on Form 10-Q for the second quarter ended June 30, 2013 is filed with the Securities and Exchange Commission.

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Use of Non-GAAP Financial Measures

In this press release we disclose “Adjusted EBITDA”, which is a non-GAAP financial measure. For purposes of SEC rules, a non-GAAP financial measure is a numerical measure of a company’s performance, financial position, or cash flows that either excludes or includes amounts that are not normally excluded or included in the most directly comparable measure, calculated and prepared in accordance with generally accepted accounting principles in the United Sates (GAAP).

EBITDA is defined as net income before (a) interest expense, net (b) income tax expense and (c) depreciation and amortization. Adjusted EBITDA is defined as EBITDA as further adjusted to eliminate non-cash share-based compensation, impairment charges, foreign exchange loss (gain) on intercompany loans, dispute settlements, cease operations – hosted services, reduction in force, value-added tax and other expense related to stock buyback. We believe that the presentation of Adjusted EBITDA included in this press release provides useful information to investors regarding our results of operations because it assists in analyzing and benchmarking the performance and value of our business. We believe that presenting Adjusted EBITDA facilitates company-to-company operating performance comparisons of companies within the same or similar industries by backing out differences caused by variations in capital structure, taxation and depreciation of facilities and equipment (affecting relative depreciation expense), which may vary for different companies for reasons unrelated to operating performance. These measures provide an assessment of controllable operating expenses and afford management the ability to make decisions which are expected to facilitate meeting current financial goals as well as achieve optimal financial performance. They provide an indicator for management to determine if adjustments to current spending decisions are needed. Furthermore, we believe that the presentation of Adjusted EBITDA has economic substance because it provides important insight into our profitability trends, as a component of net income, and allows management and investors to analyze operating results with and without the impact of depreciation and amortization, interest and income tax expense, non-cash share-based compensation, impairment charges, foreign exchange loss (gain) on intercompany loans, dispute settlements, cease operations – hosted services, reduction in force, value-added tax and other expense related to stock buyback. Accordingly, these metrics measure our financial performance based on operational factors that management can impact in the short-term, namely the operational cost structure and expenses of our business. In addition, we believe Adjusted EBITDA is used by securities analysts, investors and other interested parties in evaluating companies, many of which present an EBITDA measure when reporting their results. Although we use Adjusted EBITDA as a financial measure to assess the performance of our business, the use of Adjusted EBITDA is limited because it does not include certain material costs, such as depreciation, amortization and interest and taxes, necessary to operate our business. We disclose the reconciliation between EBITDA and Adjusted EBITDA and net income below to compensate for this limitation. While we use net income as a significant measure of profitability, we also believe that Adjusted EBITDA, when presented along with net income, provides balanced disclosure which, for the reasons set forth above, is useful to investors in evaluating our operating performance and profitability. Adjusted EBITDA included in this press release should be considered in addition to, and not as a substitute for, net income as calculated in accordance with generally accepted accounting principles as a measure of performance.

The information contained in this press release is preliminary and may be subject to significant changes and adjustments as a result of the Audit Committee’s ongoing internal investigation. Inteliquent is still investigating whether a restatement of its financial statements relating to its 2012 impairment charge could be required. To the extent Inteliquent’s $75.3 million impairment charge recognized for the year ended December 31, 2012, was overstated, a reduction of such charge would, among other matters, increase net income and impact additional financial statement accounts including the gain recognized by Inteliquent on the sale of its data business completed April 30, 2013. All results reflected in this press release should be considered preliminary until Inteliquent’s Quarterly Report on Form 10-Q for the second quarter ended June 30, 2013 is filed with the Securities and Exchange Commission.

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The following is a reconciliation of net income to EBITDA and Adjusted EBITDA:

INTELIQUENT, INC. AND SUBSIDIARIES

Preliminary Reconciliation of Non-GAAP Financial Measures to GAAP Financial Measures

(Unaudited)

(Dollars in thousands)

The information contained in this press release is preliminary and may be subject to significant changes and adjustments as a result of the Audit Committee’s ongoing internal investigation. Inteliquent is still investigating whether a restatement of its financial statements relating to its 2012 impairment charge could be required. To the extent Inteliquent’s $75.3 million impairment charge recognized for the year ended December 31, 2012, was overstated, a reduction of such charge would, among other matters, increase net income and impact additional financial statement accounts including the gain recognized by Inteliquent on the sale of its data business completed April 30, 2013. All results reflected in this press release should be considered preliminary until Inteliquent’s Quarterly Report on Form 10-Q for the second quarter ended June 30, 2013 is filed with the Securities and Exchange Commission.

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