Taxpayers increasingly are choosing to file electronically.
Electronic filing was up 2.4 per cent in 2015 from 2014. Similarly, the use of direct deposit for refund checks also is gaining in popularity. Last year, more than 86 million tax refunds were paid through direct deposit, up 2.7 per cent over 2014.
Overall, the average refund in 2015 was $2,797, a slight increase over the previous year.
"Choosing e-file and direct deposit for refunds remains the fastest and safest way to file an accurate income tax return and receive a refund,'' the IRS said on its website.
The agency expects to pay more than 90 per cent of refunds in less than 21 days.
Identity theft continues to be a problem. Sometimes the first indication is a notice from the IRS that a tax return already has been filed with a taxpayer's Social Security number.
To combat the problem, the IRS launched a public awareness campaign in November and began issuing a series of tips on how to protect data online.
"The IRS and the states have been working to get better at detecting these false returns, but as the criminals steal more and more personal data, they can do an even better job of making a tax return look legitimate,'' IRS Commissioner John Koskinen said in a statement.
"In short, the criminals are evolving, and so must we,'' he said.