Please direct your media and public relations inquiries to: mediarelations@cdw.com 800-800-4CDW CDW Announces 4.7 Percent Increase in Average Daily Sales for June Will Release Second Quarter Results on July 16, 2003 VERNON HILLS, Ill. - July 10, 2003 - CDW Corporation (Nasdaq: CDWC) today announced sales results for June 2003 of $373.4 million, compared with sales of $339.5 million for June 2002. Average daily sales for June 2003 were $17.782 million, an increase of 4.7 percent versus average daily sales of $16.977 million for June 2002. June 2003 had 21 billing days and June 2002 had 20 billing days. "We are pleased to see an increase in our sales growth rate," commented John A. Edwardson, CDW's chairman and chief executive officer. "On an average daily sales basis, our public sector business continued its strong double-digit growth and we had a small uptick in corporate sector sales." The company will release its second quarter 2003 results on Wednesday, July 16, 2003 at 4:30 p.m. Eastern Daylight Time (EDT). On July 16, 2003 at 5:00 p.m. EDT, management will review these results during a conference call. This conference call will be available via live Webcast - in listen-mode only - on the Company's Web site at CDW.com and through streetevents.com. An audio replay of the call will be available approximately two hours after the event on streetevents.com until July 31, 2003. The company plans to release July 2003 sales results on Tuesday, August 12, 2003. About CDW CDW® (Nasdaq: CDWC), ranked No. 381 on the FORTUNE 500, is a leading provider of technology solutions for businesses, government agencies and educational institutions nationwide. CDW is a principal source of technology products and services including top name brands such as APC, Apple, Cisco, HP, IBM, Microsoft, Sony, Symantec, Toshiba and ViewSonic. CDW distributes contracts to end users for customized and standardized on-site services supplied directly by providers such as HP Services and Unisys and for training programs provided by firms such as KnowledgeNet and Productivity Point International. CDW was founded in 1984 as a home-based business and today employs 3,000 coworkers whose efforts generated net sales of more than $4.2 billion in 2002. CDW's direct model offers one-on-one relationships with knowledgeable account managers; purchasing by telephone, fax, the company's award-winning www.cdw.com Web site or customized CDW@work™ extranets; custom configured solutions and same day shipping; flexible financing solutions; and pre- and post-sales technical support, with more than 100 factory-trained and A+ certified technicians on staff. Additional information can be found by visiting CDW.com.