FOR IMMEDIATE RELEASE

Investor Contact:	Media Contact:
James Stawski	Brian Crenshaw
704-319-1189	704-319-1942
jstawski@uslec.com	bcrenshaw@uslec.com

US LEC ACHIEVES OVER $95 MILLION IN REVENUE
AND GROWS EBITDA TO OVER $12 MILLION IN SECOND QUARTER OF 2005

END CUSTOMER REVENUE FOR THE QUARTER ENDED JUNE 30, 2005 CONTINUES TO BE
STRONG WITH 17% GROWTH YEAR OVER YEAR

Charlotte, N.C. (July 28, 2005) –– US LEC Corp. (Nasdaq: CLEC), a leading telecommunications carrier serving businesses and enterprise organizations throughout the Eastern United States, today announced strong results for the second quarter and six months ending June 30, 2005. The second quarter was highlighted by:

• Achieving total revenue of $95.3 million, a $3.7 million increase over the second quarter of 2004

• Reaching end customer revenue of $81.4 million, an increase of almost $12.0 million or 17%, compared with the same period last year

• Growing data revenue to $29.5 million, accounting for 31% of total revenue

• Achieving EBITDA of $12.2 million, a 13% EBITDA margin for the quarter (see definition and reconciliation of EBITDA to net cash flow from operations below)

• Expanding the Company’s business class customer base to over 24,000 and its data customer base to over 17,000 – 71% of US LEC’s business class customers selecting one or more data products

• Continuing the roll out of US LEC’s advanced IP data product set with the introduction of metro Multi-Protocol Label Switching Virtual Private Network (MPLS VPN) service and enhancing our Dynamic T^SM integrated voice and broadband Internet product to allow direct IP peering with IP PBXs using Session Initiated Protocol (SIP)

• Offering its business class customers state-of-the-art online data backup and recovery solutions

• Expanding its full suite of voice, data and Internet services into northern New Jersey, White Plains, New York and Westchester County, New York and introducing our Dynamic T^SM product line to the greater Philadelphia market

     Revenues for the quarter ended June 30, 2005, were $95.3 million, compared with $91.6 million for the quarter ended June 30, 2004, and $93.5 million reported in the first quarter of 2005. For the three months ended June 30, 2005, end customer revenue increased 17% to $81.4 million from $69.4 million in the same period of 2004. The Company reported a net loss attributable to common stockholders of ($8.9) million, or ($0.30) per share, on 30.3 million weighted average shares outstanding for the quarter ended June 30, 2005, compared with net loss attributable to common stockholders of ($5.1) million, or ($0.17) per share, on 29.9 million weighted average shares outstanding for the quarter ended June 30, 2004. EBITDA for the second quarter was $12.2 million, compared to EBITDA of $12.9 million in the second quarter of 2004, and EBITDA of $11.9 million in the first quarter of 2005.

     Revenues for the six months ended June 30, 2005 were $188.9 million, compared with $176.8 million

US LEC Announces Second Quarter 2005 Results
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July 28, 2005

for the six months ended June 30, 2004. For the six months ended June 30, 2005, end customer revenue increased 18% to $160.5 million from $136.2 million in the same period of 2004. The net loss attributable to common stockholders was ($17.9) million, or ($0.59) per share on 30.3 million weighted average shares outstanding for the six months ended June 30, 2005, compared with net loss attributable to common stockholders of ($12.3) million, or ($0.41) per share on 29.8 million weighted average shares outstanding for the six months ended June 30, 2004. EBITDA for the six months ended June 30, 2005, was $24.0 million compared with $24.3 million in the first six months of 2004.

     Commenting on the Company’s second quarter 2005 results, Aaron D. Cowell, president and chief executive officer of US LEC, said, “We are pleased with US LEC’s continuing progress. Solid customer growth, strong monthly retention and continued efforts to keep our network as efficient as possible helped us to achieve greater than 64% incremental end customer gross margins on a year over year basis. In addition, during the second quarter we surpassed the 24,000 customer milestone while maintaining our industry leading 99% monthly customer retention rate. We continue to believe this to be one of the best retention rates in the industry and reflects US LEC’s strong focus on customer service. Notably, we also achieved 28% and 20% growth in active data and voice channels, respectively, over the same period last year. On the data customer front, we achieved the 17,000 data customer milestone and continue to expand our presence in this important business segment.

     On the product front, we now offer a secure data backup and recovery product and we expanded our enhanced IP product suite with the introduction of new capabilities for our Dynamic T product and our new MPLS VPN data networking product. We will expand our enhanced IP offerings throughout our footprint, and plan to offer MPLS VPN in most of our markets by year end. Initial customer response has been good, and we believe that our enhanced IP offerings will be well received by our target business customers. Finally, we welcome our new chief financial officer, Lyle Patrick, to the US LEC team. He brings a wealth of knowledge and industry experience to the Company and we know he will make a positive contribution to increasing stakeholder value,” added Cowell.

     J. Lyle Patrick, executive vice president and chief financial officer of US LEC, added, “During the quarter, US LEC achieved total revenue of $95.3 million and EBITDA of $12.2 million, while absorbing an $8.3 million year-over-year reduction in inter-carrier revenue. We are very pleased that end customer revenue increased by $12.0 million year-over-year to reach $81.4 million, and represented over 85% of total revenue in the quarter. At a productivity level, the US LEC team has continued to consistently improve its performance by increasing end customer revenue to $74,600 per employee from $65,900 per employee one year earlier. We believe that maintaining these strong growth levels validates the strength of US LEC’s business plan and our solid execution. We have also remained diligent in our efforts to tightly manage our expenses. End customer revenue increased by $2.3 million over the first quarter while SG&A increased by $700,000, approximately half of which was related to one-time marketing expenditures. Our balance sheet reflects a strong cash position of over $35.4 million after making an $8.1 million interest payment early in the second quarter. US LEC continues to focus on revenue growth, cost control and working capital improvements and we believe we are well positioned to leverage our strengths into tangible results for 2005.”

Conference Call Information

US LEC Corp. will hold a conference call to discuss this press release on July 28, 2005, at 1:00 p.m. EST. A live broadcast of the conference call will be available online at www.uslec.com, and www.fulldisclosure.com. To listen to the live call, visit either web site at least fifteen minutes early to register, download, and install any necessary audio software. For those who cannot listen to the live broadcast, a telephone replay will be available shortly after the call through the close of business on August 3, 2005 and replay via webcast will be available through August 28, 2005.

About US LEC
Based in Charlotte, NC, US LEC is a leading telecommunications carrier providing integrated voice, data and Internet services to medium and large businesses and enterprise organizations throughout 15 Eastern states

US LEC Announces Second Quarter 2005 Results
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July 28, 2005

and the District of Columbia. US LEC services include local and long distance calling services, Voice over Internet Protocol (VoIP) service, advanced data services such as MPLS VPN, Frame Relay, Multi-Link Frame Relay and ATM, dedicated and dial-up Internet services, managed data solutions, data back-up and restoration, data center services and Web hosting. US LEC also offers selected voice services in 27 additional states and provides enhanced data services, selected Internet services and MegaPOP® (local dial-up Internet access for ISPs) nationwide. For more information about US LEC, visit www.uslec.com.

Except for the historical information contained herein, this report contains forward-looking statements, subject to uncertainties and risks, including the demand for US LEC’s services, the ability of the Company to introduce additional products, the ability of the Company to successfully attract and retain personnel, competition in existing and potential additional markets, uncertainties regarding its dealings with ILECs and other telecommunications carriers and facilities providers, regulatory uncertainties, the possibility of adverse decisions related to reciprocal compensation and access charges owing to the Company, as well as the Company’s ability to begin operations in additional markets. These and other applicable risks are summarized in the “Caution Regarding Forward-Looking Statements and Risk Factors” sections and elsewhere in the Company’s Annual Report on Form 10-K for the period ended December 31, 2004, and in subsequent reports, which are on file with the Securities and Exchange Commission.

US LEC is a registered service mark of US LEC Corp. US LEC and Design (R) is a registered service mark and trademark of US LEC Corp. StarNet™, Fastnet (SM) and MegaPOP(R) are service marks of US LEC Corp.

-END-

US LEC Announces Second Quarter 2005 Results
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July 28, 2005

US LEC Corp. and Subsidiaries
Condensed Consolidated Statements of Operations
(In Thousands, Except Per Share Data)
(Unaudited)

	Three months ended						Six months ended
	June 30,						June 30,
	2005			2004			2005			2004
Revenue	$	95,343		$	91,633		$	188,858		$	176,820
Network Expenses (excluding depreciation and amortization shown below)		46,597			42,322			92,381			83,772
Depreciation and Amortization		12,638			11,822			25,569			24,307
Selling, General and Administrative Expenses		36,590			36,371			72,457			68,788
Income/(Loss) from Operations		(482	)		1,118			(1,549	)		(47	)
Net Interest Expense		4,279			2,276			7,991			4,428
Net Loss		(4,761	)		(1,158	)		(9,540	)		(4,475	)
Preferred Stock Dividends		(4,033	)		(3,800	)		(8,007	)		(7,544	)
Preferred Stock Accretion of Issuance Costs		(155	)		(146	)		(307	)		(289	)
Net Loss Attributable to Common Stockholders	$	(8,949	)	$	(5,104	)	$	(17,854	)	$	(12,308	)
Net Loss Attributable to Common Stockholders Per Common Share
Basic and Diluted	$	(0.30	)	$	(0.17	)	$	(0.59	)	$	(0.41	)
Weighted Average Number of Shares Outstanding
Basic and Diluted		30,295			29,853			30,291			29,802

EBITDA consists of earnings (loss) before interest income and expense, income taxes, depreciation and amortization. EBITDA as used by the Company may be different than similarly used measures by other companies and is not a measure of financial performance under GAAP. Management believes EBITDA is a useful measure of the Company’s liquidity and is used by investors and analysts to evaluate companies in our industry. EBITDA is reconciled to net cash provided by operating activities as follows:

	Three months ended						Six months ended
	June 30,						June 30,
	2005			2004			2005			2004
Income/(Loss) from Operations	$	(482	)	$	1,118		$	(1,549	)	$	(47	)
Depreciation and Amortization		12,638			11,822			25,569			24,307
EBITDA		12,156			12,940			24,020			24,260
Changes in Working Capital		(9,471	)		(4,676	)		(11,541	)		(6,845	)
Net Interest Expense		(4,279	)		(2,276	)		(7,991	)		(4,428	)
Miscellaneous Other		(95	)		169			(219	)		44
Net Cash Provided by Operating Activities	$	(1,689	)	$	6,157		$	4,269		$	13,031

US LEC Announces Second Quarter 2005 Results
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July 28, 2005

US LEC Corp. and Subsidiaries
Condensed Consolidated Balance Sheets
(In Thousands, Except Per Share Data)
(Unaudited)

	June 30,			December 31,
	2005			2004
Assets
Cash and cash equivalents	$	35,464		$	48,232
Restricted cash		169			169
Accounts receivable, net		66,618			60,745
Property and equipment, net		148,756			158,617
Deferred income taxes		5,593			1,507
Other assets		26,803			29,041
Total Assets	$	283,403		$	298,311
Liabilities and Stockholders’ Deficiency
Accounts payable	$	15,101		$	21,466
Notes Payable		—			980
Deferred revenue		13,177			13,573
Accrued network costs		25,981			28,730
Accrued expenses		27,416			26,913
Deferred income taxes		5,593			1,507
Long-term debt		149,363			149,288
Total Liabilities		236,631			242,457
Series A Redeemable Convertible Preferred Stock		269,472			261,158
STOCKHOLDERS’ DEFICIENCY
Common Stock — Class A		305			303
Additional paid-in capital		92,824			92,368
Accumulated Deficit		(315,829	)		(297,975	)
Total Stockholders’ Deficiency		(222,700	)		(205,304	)
Total Liabilities, Convertible Preferred Stock and Stockholders’ Deficiency	$	283,403		$	298,311

US LEC Announces Second Quarter 2005 Results
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July 28, 2005

US LEC Corp. and Subsidiaries
Quarterly Statistical Highlights
(Unaudited)

	June 30,			March 31,			December 31,			September 30,			June 30,
	2005			2005			2004			2004			2004
Revenue (in 000s):
End Customer Revenue
Voice Monthly Recurring Charges	$	39,515		$	37,836		$	37,044		$	36,628		$	35,414
Data Monthly Recurring Charges		29,476			28,391			26,062			23,449			22,132
Long Distance		12,421			12,892			11,709			12,876			11,879
		81,412			79,119			74,815			72,953			69,425
Percent of Total Revenue		85	%		85	%		81	%		84	%		76	%
Carrier Charges
Carrier Access		8,826			8,994			12,345			8,702			15,183
Reciprocal Compensation		2,165			2,296			2,134			2,175			4,105
		10,991			11,290			14,479			10,877			19,288
Percent of Total Revenue		12	%		12	%		16	%		12	%		21	%
Other Revenue (1)		2,940			3,107			2,806			3,432			2,920
Percent of Total Revenue		3	%		3	%		3	%		4	%		3	%
Total Revenue	$	95,343		$	93,516		$	92,100		$	87,262		$	91,633
Customers (2):
Total Customers		37,998			38,071			38,273			36,672			36,045
Business Class Customers		24,213			23,420			22,324			20,631			19,397
Business Class Customers Purchasing Data Services		17,101			14,007			13,294			12,048			11,037
Shared Hosting/Dial Up Customers		13,785			14,651			15,949			16,041			16,648
Active Channels (3):
Voice		460,185			439,032			426,422			404,169			381,905
Data		348,357			327,153			303,802			284,830			273,009
Total active channels		808,542			766,185			730,224			688,999			654,914
Statistical Data:
Central Offices		27			27			27			27			27
Number of employees		1,092			1,078			1,065			1,034			1,054
Number of sales and sales support employees		476			471			460			451			458
End Customer Revenue/Employee (in 000s)	$	74.6		$	73.4		$	70.2		$	70.6		$	65.9

(1) Other revenue is derived from wholesale customers, installation revenue and other miscellaneous sources.

(2) Net of the following adjustments: a 307 decrease in business class customers and a 1,611 increase in data customers in the second quarter of 2005 as a result of billing improvements to better identify customers by their service location rather than their billing location.

(3) Shared hosting and Dial-Up Internet Access are not included in Active Channels.