Here are a few key tax-related deadlines for businesses during Q1 of 2018. JAN. 31: File 2017 Forms W-2 with the Social Security Administration and provide copies to employees, and provide copies of 2017 Forms 1099-MISC to recipients. FEB. 28: File 2017 Forms 1099-MISC if paper filing. (Forms 1099-MISC reporting nonemployee compensation in Box 7 must be filed by Jan. 31.) MAR. 15: If a calendar-year partnership or S corp., file or extend your 2017 tax return. Contact us to learn more about the filing requirements and ensure you’re meeting all applicable deadlines.