January 31

• Individuals: Filing a 2018 income tax return (Form 1040) and paying tax due, to avoid penalties for underpaying the January 15 installment of estimated taxes.

• Businesses: Providing Form 1098, Form 1099 (except for those that have a February 15 deadline) and Form W-2G to recipients. Filing Form 1099 if it includes payments for nonemployee compensation in Box 7.

• Employers: Providing 2018 Form W-2 to employees; reporting income tax withholding and FICA taxes for fourth quarter 2018 (Form 941); and filing an annual return of federal unemployment taxes (Form 940) and paying any tax due.

• Employers: Filing 2018 Form W-2 (Copy A) and transmittal Form W-3 with the Social Security Administration.

February 15

• Businesses: Providing Form 1099-B, 1099-S and certain Forms 1099-MISC (those in which payments in Box 8 or Box 14 are being reported) to recipients. 
• Individuals: Filing a new Form W-4 to continue exemption for another year, if you claimed exemption from federal income tax withholding in 2018.

March 11

• Businesses: Filing Form 1098, Form 1099 (other than those with a January 31 or February 15 deadline) and Form W-2G and transmittal Form 1096 for interest, dividends and miscellaneous payments made during 2018. (Electronic filers can defer filing to April 1.)

April 1

• Electronically file 2018 Form 1096, Form 1098, Form 1099 (except if an earlier deadline applies) and Form W-2G.

April 15

• Individuals: Filing a 2018 income tax return (Form 1040, Form 1040A or Form 1040EZ) or filing for an automatic six-month extension (Form 4868), and paying any tax due. (See June 17 for an exception for certain taxpayers.) 
• Individuals: Paying the first installment of 2019 estimated taxes, if not paying income tax through withholding (Form 1040-ES).
• Individuals: Making 2018 contributions to a traditional IRA or Roth IRA (even if a 2018 income tax return extension is filed).
• Individuals: Making 2018 contributions to a SEP or certain other retirement plans (unless a 2018 income tax return extension is filed).
• Individuals: Filing a 2018 gift tax return (Form 709) or filing for an automatic six-month extension (Form 8892), and paying any gift tax due; or filing for an automatic six-month extension (Form 4868) to extend both Form 1040 and, if no gift tax is due, Form 709.
• Household employers: Filing Schedule H (Form 1040), if wages paid equal $2,100 or more in 2018 and Form 1040 is not required to be filed. For those filing Form 1040, Schedule H is to be submitted with the return and is thus extended to the due date of the return.
• Trusts and estates: Filing an income tax return for the 2018 calendar year (Form 1041) or filing for an automatic five-and-a-half month extension to October 1 (Form 7004), and paying any income tax due.
• Calendar-year corporations: Filing a 2018 income tax return (Form 1120) or filing for an automatic six-month extension (Form 7004), and paying any tax due.
• Calendar-year corporations: Paying the first installment of 2019 estimated income taxes.

April 30

• Employers: Report income tax withholding and FICA taxes for first quarter 2018 (Form 941), and pay any tax due. (See exception below under “May 10.”)

May 10

• Individuals: Reporting April tip income, $20 or more, to employers (Form 4070). 
• Employers: Reporting income tax withholding and FICA taxes for first quarter 2019 (Form 941), if you deposited on time and in full all of the associated taxes due.

June 17

• Individuals: Filing a 2018 individual income tax return (Form 1040) or filing for a four-month extension (Form 4868), and paying any tax and interest due, if you live outside the United States. 
• Individuals: Paying the second installment of 2019 estimated taxes, if not paying income tax through withholding (Form 1040-ES).
• Calendar-year corporations: Paying the second installment of 2019 estimated income taxes.
• Individuals: Reporting April tip income, $20 or more, to employers (Form 4070). 
• Employers: Reporting income tax withholding and FICA taxes for first quarter 2019 (Form 941), if you deposited on time and in full all of the associated taxes due.
• Individuals: Reporting April tip income, $20 or more, to employers (Form 4070). 
• Employers: Reporting income tax withholding and FICA taxes for first quarter 2019 (Form 941), if you deposited on time and in full all of the associated taxes due.

July 31

• Report income tax withholding and FICA taxes for second quarter 2019 (Form 941), and pay any tax due. (See the exception below, under “August 10.”)
• File a 2018 calendar-year retirement plan report (Form 5500 or Form 5500-EZ) or request an extension.

August 12

• Report income tax withholding and FICA taxes for second quarter 2019 (Form 941), if you deposited on time and in full all of the associated taxes due.

September 16

• If a calendar-year C corporation, pay the third installment of 2019 estimated income taxes.
• If a calendar-year S corporation or partnership that filed an automatic six-month extension.
• File a 2018 income tax return (Form 1120S, Form 1065 or Form 1065-B) and pay any tax, interest and penalties due.

• Make contributions for 2018 to certain employer-sponsored retirement plans.

October 15

• If a calendar-year C corporation that filed an automatic six-month extension:
  • File a 2018 income tax return (Form 1120) and pay any tax, interest and penalties due.
  • Make contributions for 2018 to certain employer-sponsored retirement plans.

October 31

• Report income tax withholding and FICA taxes for third quarter 2019 (Form 941) and pay any tax due. (See exception below under “November 13.”)

November 13

• Report income tax withholding and FICA taxes for third quarter 2019 (Form 941), if you deposited on time and in full all of the associated taxes due.

December 16

• If a calendar-year C corporation, pay the fourth installment of 2019 estimated income taxes.