The days of tax-free online shopping could be numbered.

A bill to impose sales tax on Internet purchases took one step closer to being passed Wednesday, when the Senate voted 75-22 in favor of considering The Marketplace Fairness Act. A vote on passage could come this week.

The bill is supported by the White House and e-commerce giant Amazon.com and embraced by brick-and-mortar retailers, their trade association and the National Conference of State Legislatures. But it has been sharply criticized by online merchants led by eBay, as well as anti-tax advocates.

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Despite the debate over the issue, experts say it won't change the way most Americans use the Internet to shop.



"Ultimately, customers are used to paying taxes on goods they purchase, just not necessarily online," said Clark Fredricksen, vice president of communications at eMarketer. "It wouldn't be surprising to see some outcry but in fact very little impact on actual sales."

"Consumers only care on big ticket items," said Tom Forte, Internet analyst at Telsey Advisory Group. "If you think about why people purchase from catalogs or e-commerce companies, selection and convenience are numbers one and two... Price is not as important."

"On an average basket size of $40 to $50 it's not going to have an impact," said Aaron Kessler, senior analyst at Raymond James & Associates.

Fredricksen said it also wouldn't stop the pervasive practice of showrooming, where customers visit brick-and-mortar stores to see an item, then buy it somewhere else.

"Price comparison is only one component of why consumers showroom," he said. "Showrooming is a broader phenomenon encouraged by rapid adoption of smartphones and growing use of mobile phones as purchasing and shopping devices."

Even the National Retail Federation agreed that, sales tax or not, showrooming is probably here to stay. "I think retailers will adapt to it," said David French, the group's senior vice president of government relations. "What this will do is eliminate the built-in price advantage online retailers have," he said.