February 28, 2020 If you're currently required to file Form 944, Employer's Annual Federal Tax Return, but estimate your tax liability to be more than $1,000, you may be eligible to update your filing requirement to Form 941, Employer's Quarterly Federal Tax Return. If you're an employer required to file a Form 941 but estimate your tax liability will be $1,000 or less for the tax year, you may be eligible to switch to Form 944. To request a change, send a written request, postmarked by March 15 or call the IRS at 800-829-0115 by April 1. The agency will send a written notice if it changes your filing requirement. For more information visit IRS.gov.