Exhibit 99.1

TNS, Inc. Announces First Quarter 2006 Financial Results

RESTON, Va. — May 4, 2006 —TNS, Inc. (NYSE: TNS), a leading provider of business-critical, cost-effective data communications services for transaction-oriented applications, today reported its first quarter 2006 results.

Total revenue for the first quarter of 2006 increased 4.4% to $65.9 million from first quarter 2005 revenues of $63.1 million. Gross margin in the first quarter of 2006 was 49.8%, a decrease of approximately 230 basis points from first quarter 2005 gross margin of 52.1%.

Earnings before interest, taxes, depreciation, and amortization (EBITDA) before stock compensation expense for the first quarter of 2006 was $13.6 million versus $16.4 million for the first quarter of 2005.  Included in selling, general and administrative expenses (SG&A) for the first quarter of 2006 is a pre-tax charge to earnings of approximately $0.7 million, comprised of an approximate $0.5 million charge related to a reserve for litigation that arose during the first quarter and an approximate $0.2 million charge for legal expenses incurred by the special committee of our board of directors.  Excluding the $0.7 million pre-tax SG&A charge, first quarter 2006 EBITDA before stock compensation expense was $14.3 million.  As reported last year, SG&A for the first quarter of 2005 included a pre-tax benefit to earnings of $1.0 million, comprised of a $3.2 million charge related to a legal settlement and a $4.2 million benefit from a reduced state sales tax liability assessment.  Excluding the $1.0 million pre-tax SG&A benefit, first quarter 2005 EBITDA before stock compensation expense was $15.4 million.

Adjusted earnings for the first quarter of 2006 was $3.6 million, or $0.15 per share, compared to adjusted earnings for the first quarter of 2005 of $6.3 million, or $0.22 per share.  Excluding the $0.7 million pre-tax SG&A charge, adjusted earnings for the first quarter of 2006 was $4.0 million or $0.17 per share.  Excluding the $1.0 million pre-tax SG&A benefit, adjusted earnings for the first quarter of 2005 was $5.7 million or $0.20 per share. (EBITDA before stock compensation expense, adjusted earnings and adjusted earnings per share are non-GAAP measures.  See “Financial Measures” below for a discussion of these metrics.)

First quarter 2006 GAAP net loss was $0.5 million, or $0.02 per share, versus first quarter 2005 GAAP net income of $1.5 million, or $0.05 per share. Excluding the $0.7 million pre-tax SG&A charge, first quarter 2006 net loss was approximately $0.1 million, or $0.00 per share.    Excluding the $1.0 million pre-tax SG&A benefit, first quarter 2005 net income was $0.9 million, or $0.03 per share.

The Company adopted SFAS No. 123 (revised 2004), “Share-Based Payment” (SFAS No. 123R), on January 1, 2006.  The impact on first quarter 2006 GAAP net loss was approximately $0.3 million.

As previously announced in the first quarter of 2006, the Company won a multi-year contract extension with TSYS Acquiring Solutions, formerly known as Vital Processing Services, to provide additional domestic and international transaction transport network services.

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Jack McDonnell, Chairman and CEO, commented, “TNS’ first quarter revenues reached the lower end of our guidance.  Our revenue increase was driven by increased demand for our SS7 services in our telecommunications services division, as well as continued strong demand for the services provided by our financial services division and our international services division.  Adjusted earnings were challenged by unexpected expenses related to a reserve for litigation that arose during the first quarter and legal expenses incurred by the special committee of our board of directors.   We continue to focus on growing all of our divisions and making 2006 a successful year.”

TNS reaffirms its outlook for the following:

Outlook for the second quarter of 2006:

Henry Graham, Executive Vice President and CFO, commented, “Our telecommunications, financial and international services revenues continue to contribute to TNS’ growth and now represent 71.5% of total revenue.  For 2006, we continue to target 14-16% revenue growth and 8-12% adjusted earnings growth and believe we have a plan in place to capture our growth opportunities in each division to attain these objectives.”

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In addition to the results presented in accordance with generally accepted accounting principles, or GAAP, in this press release, the Company presents EBITDA before stock compensation expense, adjusted earnings and adjusted earnings per share, which are non-GAAP measures. EBITDA is determined by taking income from operations and adding back certain non-cash items, including amortization of intangible assets, depreciation and amortization of property and equipment and stock compensation expense. Adjusted earnings is determined by taking pretax income or loss after equity in net loss of unconsolidated affiliates and adding back certain non-cash items, including amortization of intangible assets, stock compensation expense and the write-off of debt issuance costs, and the result is tax effected at a 38% rate. The Company believes that these non-GAAP measures, viewed in addition to and not in lieu of the Company’s reported GAAP results, provide useful information to investors because these metrics provide a more focused measure of operating results. These metrics are an integral part of the Company’s internal reporting to measure operations of the Company and the performance of senior management. A reconciliation to comparable GAAP measures is available in the accompanying schedule. The non-GAAP measures presented herein may not be comparable to similarly titled measures presented by other companies.

TNS will hold a conference to discuss first quarter 2006 results on Thursday, May 4, 2006, at 5:00 p.m. Eastern Time.  The dial-in number for the conference call is 617-213-8857, passcode # 27393500. The call is also being webcast, and there will be an accompanying slide presentation, which can be accessed at www.tnsi.com.  For those who cannot listen to the live broadcast, a replay of the call will be available from May 4, 2006 at 7:00 p.m. Eastern Time through June 4, 2006, and can be accessed by dialing 617-801-6888, passcode 45953501.

TNS is one of the leading providers of business-critical, cost-effective data communications services for transaction-oriented applications and operates through its wholly owned subsidiary Transaction Network Services, Inc. TNS provides rapid, reliable and secure transaction delivery platforms to enable transaction authorization and processing across several vertical markets and trading communities.

Since its inception in 1990, TNS has designed and implemented multiple data networks, each designed specifically for the transport of transaction-oriented data. TNS’ networks support a variety of widely accepted communications protocols and are designed to be scalable and accessible by multiple methods. TNS’ network technologies have been deployed in the United States and internationally, and TNS’ networks have become preferred networks servicing the trading community, wireless and wireline carriers, and the card processing and dial-up automated teller machine markets. For further information about TNS, please refer to www.tnsi.com.

The statements contained in this release that are not historical facts are forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995.  These forward-looking statements are based on current expectations, forecasts and assumptions that are subject to risks and uncertainties that could cause actual results to differ materially from those set forth in, or implied by, the forward-looking statements. The Company has attempted, whenever possible, to identify these forward-looking statements using words such as “may,” “will,” “should,” “projects,” “estimates,” “expects,” “plans,” “intends,” “anticipates,” “believes,” and variations of these words and similar expressions.  Similarly, statements herein that describe

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the Company’s business strategy, prospects, opportunities, outlook, objectives, plans, intentions or goals are also forward-looking statements.  Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including:  the Company’s reliance upon a small number of customers for a significant portion of its revenue; competitive factors such as pricing pressures; the Company’s ability to grow its business domestically and internationally by generating greater transaction volumes, acquiring new customers or developing new service offerings; fluctuations in the Company’s quarterly results because of the seasonal nature of the business and other factors outside of the Company’s control; the Company’s ability to identify, execute or effectively integrate future acquisitions; the Company’s ability to adapt to changing technology; additional costs related to compliance with the Sarbanes-Oxley Act of 2002, any revised New York Stock Exchange listing standards, Securities and Exchange Commission (SEC) rule changes or other corporate governance issues; and other risk factors described in the Company’s annual report on Form 10-K filed with the SEC on March 16, 2006.  In addition, the statements in this press release are made as of May 4, 2006.  The Company expects that subsequent events or developments will cause its views to change.  The Company undertakes no obligation to update any of the forward-looking statements made herein, whether as a result of new information, future events, changes in expectations or otherwise.  These forward-looking statements should not be relied upon as representing the Company’s views as of any date subsequent to May 4, 2006.

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TNS, Inc.

Condensed Consolidated Statements of Operations

(In thousands, except share and per share amounts)

(Unaudited)

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TNS, Inc.

Condensed Consolidated Balance Sheets

(In thousands)

(Unaudited)

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TNS, Inc.

Condensed Consolidated Statement of Cash Flows

(In thousands)

(Unaudited)

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TNS, Inc.

Reconciliation of Non-GAAP Information

(In thousands, except share and per share amounts)

(Unaudited)

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