When are corporate taxes due? Tax return deadlines 2021

When reviewing the 2020 tax dates (due in 2021), it’s important to keep in mind some critical changes to the 2021 tax due dates. We created a summary of due dates to answer common questions from your clients including, “when are business taxes due,” “when is LLC tax return due,” and “when are small business taxes due?”

Important: It’s always recommended to check the IRS website for the most up-to-date information on tax due dates. The dates below are from the most recent IRS data released October 6, 2020. 2020 was a lesson in remaining flexible and expecting changes, so keep your firm and clients safe by checking in regularly with the IRS.

Updates and Reminders for 2021

Form 1040-SR

This is the U.S. Tax Return for Seniors, introduced in 2020. For clients aged 65 or older, they can use this form that generally mirrors Form 1040.

Forms 1040A and 1040-EZ

Neither of these forms have been available since 2019. Instead, individuals must file either form 1040 or 1040-SR.

Extensions for Individuals and Businesses Impacted by California Wildfires and Hurricane Delta

People and corporations affected by the California wildfires who had a valid extension to file their 2019 tax returns by October 15, 2020 now have until January 15, 2021 to file their returns.

For those affected by Hurricane Delta with valid extensions to file by October 15 may file their returns by February 16, 2021.

Due Dates for the 2021 Calendar Year

In order of date, here are all of the 2021 deadlines for those who pay their taxes within the calendar year.

March 1

Forms: 1099 and 1096

March 15

Forms: 1065 Partnerships and 1120 Series

Exception: File an automatic 6-month extension, then your filing deadline will instead be September 15, using form 7004.

March 31

Forms: 1099 and 1096 via e-file

Exception: Form 1099-NEC

April 15

Form: C Corporations

Form: 1040

Form: First-quarter tax payments for 2021

Form: FinCen 114 or FBAR

June 15

Form: Second-quarter tax payments for 2021

Form: Expat individual returns (can file 4868 for four-month extension)

August 2

Form: 5500 series (Employee Benefit Plan)

September 15

Form: 1065 extension

Form: Third-quarter tax payments for 2021

Form: Corporate extension from the 1120 series

October 15

Form: 1040 extension

Form: 1120 extension

Form: FinCen 114 or FBAR extension

November 15

Form: 5500 series (Employee Benefit Plan) extension

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2021 Tax Return Due Dates for Fiscal Year Filers

If you file your tax returns based on a fiscal year instead of the calendar year, you should change some of the deadlines mentioned above.


Form: 1065

Deadline: 15th day of the third month after the end of the tax year

Corporations and S Corporations

Form: 1120 (or Form 7004)

Deadline: 15th day of the fourth month after the tax year

Exception: Corporations with a fiscal year ending June 30th must file by the 15th day of the 3rd month after the end of it tax year.

Form: 1120-S (or Form 7004) and Shareholder Copy of 1120-S (Schedule K-1)

Deadline: 15th day of the third month after the end of the tax year

Form: Estimated tax payments

Deadlines: 15th day of the fourth, sixth, ninth, and 12th months of the tax year

Form: 2553

Deadline: No more than 2 months and 15 days after the beginning of the tax year

Reminder for Individual 2021 Tax Return Due Dates

It’s recommended that you always double check with the IRS in regards to the tax return due dates and deadlines. If you are filing, it’s recommended that you connect with a professional CPA or enrolled agent to have your information reviewed.

Our Jetpack Workflow community is full of incredibly talented accounting professionals, and we feature them with weekly interviews on our Growing Your Firm Podcast! Subscribe to our weekly newsletter to be the first to know about a new episode with a firm owner you’ll love.

Recommendations for Accounting Firm Owners

If you’re an accounting firm that is collecting tax information, we recommend to call, email, or send a letter at the end of the year to remind and inform your clients of any changes, and the required tax information they will need to submit for the following year’s tax due dates.

Use the end time frame (or beginning of the year) to discuss the tax strategy that you’re going to deploy for your clients.

If you’re looking for resources on how to add advisory services, or enter into value based conversations for accounting firm clients, you can view our full interview series on the Growing Your Firm Podcast.

Strategies to Manage Tax Return Due Dates in 2021

If you’re managing a significant number of clients, with recurring due dates, then a workflow software solution can help you improve profitability and capacity.

We recommend tracking the following metrics:

  • Turn-around time

  • Time spent per tax return per client

  • Profitability per job

It’s critical to track these metrics as you continue to grow your accounting firm, so that you can increase profitability as you scale and add more clients.

We’ve created 32 free templates you can use to track tasks for all of your clients. Some of the tax-based workflow templates in the download include:

  • Annual Sales Tax

  • Returns

  • Year-End Estimated Future Tax Payment

  • Amend Tax Return

  • General Tax Return

Download them today for free!

Want to break free from spreadsheets and keep all of your client and workflow data in one place?

Try our 14-day free trial today, and say goodbye to tracking your work in spreadsheets.

Jetpack Workflow does not provide tax, legal or accounting advice. This material has been prepared for informational purposes only, and is not intended to provide, and should not be relied on for, tax, legal or accounting advice. You should consult your own tax, legal and accounting advisors before engaging in any transaction.

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