The IRS will begin accepting 2016 tax returns on Jan. 23, and this year’s deadline is April 18 – not 15 – because the deadline arrives on a weekend and is followed by the Emancipation Day holiday in Washington.

Expect delays if you’re getting a 2017 refund – because of holidays for Presidents’ Day on Feb. 20 and processing times for the federal government and banks. The IRS, for instance, instituted some antifraud measures that may delay millions of refunds until Feb. 27, more than a month after tax-filing season opens, the agency said.

If you’re checking for an estimated refund date, you can use the agency’s online “Where’s My Refund?” tool – located at IRS.gov/refunds – anytime after Feb. 15.

Anyone who claims the earned income tax credit or the additional child tax credit will likely have their refund held until at least Feb. 15.

IRS Commissioner John Koskinen said taxpayers who file electronically with their own tax software need to have last year’s return handy.

“If you’re changing tax-software products this filing season, make sure you have a copy of your prior-year return on hand,” he said. “You may be asked to enter your 2015 adjusted gross income. This helps verify your identity before you e-file.”

The IRS paid refunds on 73 percent of last year’s 153 million returns, with refunds averaging $2,857, Koskinen said, and the agency expects similar numbers this year.

Taxpayers who can’t find an answer on IRS.gov can call the IRS at (800) 829-1040 Monday through Friday from 7 a.m. to 7 p.m.

Taxpayers who can’t resolve their issue online or by phone can schedule an appointment at an IRS Taxpayer Assistance Center.

Use the “contact your local office” tool on IRS.gov to find the closest office or call (844) 545-5640.

There’s also Free File, free tax-preparation software available to those earning less than $64,000 annually. After Friday, you can download the free software at www.IRS.gov/freefile or www.freefilealliance.org. The downloadable versions of Free File Fillable Forms will be available Jan. 23.

The Free File Alliance is a nonprofit coalition of industry-leading tax-software companies partnered with the IRS to provide free electronic tax services.