How unpleasant is it to fill out federal tax forms? Unpleasant enough that Americans are about evenly divided when asked whether they’d prefer a trip to the dentist.

And that may be giving the tax man too much credit.

“It’s pretty painless — until you get the bill,” said Matthew F. Krische, a Lawrence dentist who hires accountants to tackle his piles of paperwork. “And you don’t get nitrous oxide to do your taxes, so going to the dentist has the potential to feel better.”

Taxpayers have until Friday to file, and millions — Krische notwithstanding — are scrambling to meet the deadline.

Nearly a third of the 133 million income tax returns expected this year will come in to the Internal Revenue Service during the last two to three weeks, IRS spokesman Eric Smith said. The IRS expects nearly 9 million more to file extensions so that they can file late returns, while another 2 million to 3 million will be expected to miss the due date.

“If there’s a deadline, some people will do almost anything to avoid it,” Smith said.

It’s easy to see why so many wait to file their taxes.

Seven in 10 people surveyed said their federal taxes were too complicated, according to a poll conducted for The Associated Press by Ipsos-Public Affairs.

The survey found that 49 percent would prefer a trip to the dentist while 48 percent would rather prepare their taxes.

“To be mentioned in the same breath as taxes — what a wonderful compliment,” Krische said Monday, laughing as he tended to administrative duties in his dental office.

Simplifying the tax system is the goal of a federal panel that will be collecting information the next few months and is expected to offer recommendations by midsummer.