2021 Q4 tax calendar: Key deadlines for businesses and other employers

Here are some of the key tax-related deadlines affecting businesses and other employers during the fourth quarter of 2021. Keep in mind that this list isn’t all-inclusive, so there may be additional deadlines that apply to you. Contact us to ensure you’re meeting all applicable deadlines and to learn more about the filing requirements.

Note: Certain tax-filing and tax-payment deadlines may be postponed for taxpayers who reside in or have a business in federally declared disaster areas.

Friday, October 15

• If a calendar-year C corporation that filed an automatic six-month extension:
  • File a 2020 income tax return (Form 1120) and pay any tax, interest and penalties due.
  • Make contributions for 2020 to certain employer-sponsored retirement plans.

Monday, November 1

• Report income tax withholding and FICA taxes for the third quarter of 2021 (Form 941) and pay any tax due. (See exception below under “November 10.”)

Wednesday, November 10

• Report income tax withholding and FICA taxes for the third quarter of 2021 (Form 941) if you deposited on time (and in full) all of the associated taxes due.

Wednesday, December 15

• If a calendar-year C corporation, pay the fourth installment of 2021 estimated income taxes.

Friday, December 31

• Establish a retirement plan for 2021 (generally other than a SIMPLE, a Safe-Harbor 401(k) or a SEP).

Contact us if you’d like more information about the filing requirements and to ensure you’re meeting all applicable deadlines.

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