More U.S. taxpayers filing online

During the first quarter, nearly 39 percent of respondents to a survey said they planned to file their federal taxes online this year, up from 37 percent last year and approximately 28 percent three years ago, according to the Consumer Internet Barometer.

The barometer, released Monday and produced by the Conference Board and Taylor Nelson Sofres, found that approximately two-thirds of the 10,000 households surveyed have filed their taxes online for at least three consecutive years.

"The speed and convenience are helping to spur people to make the transition, but it's a slow process," said Lynn Franco, director of the Conference Board Consumer Research Center.

Concern about online security is one of the issues tempering the rapid adoption of online tax filing, Franco noted.

More than 68 percent of survey respondents were "somewhat" or "extremely" concerned with security issues related to online tax filing, according to the results. That degree of concern was also present in last year's results.

Nonetheless, Franco expects the number of online taxpayers to exceed more than 50 percent within the next several years.

"Once they get past their security concerns, it should reach that level," Franco said. "You can see from the results there are a lot of repeat users."