The Internal Revenue Service kicked off the 2017 tax season Monday, January 23, although the IRS won’t be able to process some returns until the week of February 15.

The IRS is anticipating it will receive more than 153 million tax returns this year. Taxpayers get a few extra days, until Tuesday, April 18, to file their 2016 tax returns, because April 15 falls on a Saturday, and April 17 is Emancipation Day, a holiday that is observed in Washington, D.C.

Taxpayers and preparers who file returns claiming the Earned Income Tax Credit and the Additional Child Tax Credit will see some delays in getting their tax returns processed. A 2016 law requires the IRS to hold refunds claiming the EITC and the ACTC until February 15 to safeguard against identity theft. However, the IRS is encouraging taxpayers to file as they normally would, including returns claiming the EITC or ACTC.

The IRS will begin releasing EITC and ACTC refunds on February 15, but is warning taxpayers the refund probably won’t start arriving in their bank accounts or on their debit cards until the week of February 27. For EITC and ACTC filers, the three-day holiday weekend involving President’s Day could also affect the timing of their tax refunds.

Michael Cohn, editor-in-chief of AccountingToday.com, has been covering business and technology for a variety of publications since 1985.