Traffic to tax preparation sites on the Internet skyrocketed last week as surfers logging on at home sought to beat the upcoming U.S. tax-filing deadline on April 15, Internet audience measurement service Nielsen/NetRatings said on Thursday.

During the week ending April 7, traffic at H&R Block Inc.'s Web site jumped 51 percent. NetRatings said the site attracted 338,000 Web surfers compared with 224,000 visitors the previous week. 

Traffic to Intuit Inc.'s TurboTax.com site soared 46 percent week over week to 534,000 at-home surfers, with the most popular pages featuring online tax filing forms. 

Intuit's ShopIntuit.com site spiked by 35 percent as 194,000 unique visitors logged on to the site to download tax preparation software. 

Traffic to the IRS Web site grew 28 percent to more than 1.2 million. About 22 percent of the surfers accessed tax information for individual filers, while 20 percent sought information on electronic preparation and filing of income taxes. 

Rounding out the list of various tax sites that had increases in traffic, more than 1.7 million surfers logged on to Intuit's Intuit's Quicken.com as traffic jumped 25 percent compared with the previous week. 

"With just a few days to go before the tax deadline, the Web expedites the filing process and makes tax preparation less burdensome, giving surfers added incentive to e-file," said Patrick Thomas, senior Internet analyst at NetRatings.