NEW YORK (CNN/Money) - You've double-checked your 1040 and have your accountant on speed dial but you forgot one thing -- to make copies of your tax returns.

Officials at Staples are hoping they can help.

From 8 a.m. until 11:45 p.m. ET Friday at select post offices in four major cities, the office supply retailer will set up banks of copiers, allowing customers to make copies of their 2004 returns. It's the first year the nation's No. 1 office supply chain is offering the service.

"We know people are rushed so we're making it convenient and easy for them all day on tax day," John Burke, senior vice president of business services at Staples, said in a statement.

The machines will be available outside post offices in New York, Chicago, Los Angeles and Boston. The Framingham, Mass.-based retailer started the service at retail stores on April 1 and will continue to provide free copies at its 1,200 locations until Friday's tax deadline.

While the promotion might help tax procrastinators this year, the entire filing process seems to be evolving towards e-filing, according to the Internal Revenue Service.

The agency said that as of April 8, 63 percent of all tax returns were filed electronically, noting some 55.8 million Americans have filed electronically so far this year, up 8 percent from last year.

Shares of Staples (up $0.24 to $31.05, Research), the largest office supply chain in the country ahead of Office Depot, rose in afternoon trading on Nasdaq.

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