Filing Your Income Taxes

Filing Your Income Tax Return

Tax Deadlines in 2021 for 2020 Tax Year

Tax Deadlines in 2021 for 2020 Tax Year
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The Internal Revenue Service's ​April 15​ tax filing deadline might be the only due date that rings a bell for many taxpayers, but there are additional filing deadlines that can apply. Different types of income are reported on different kinds of income tax returns that have different due dates. The filing process got a streamlined makeover in 2018 tax year when a newly designed 1040 form was introduced that might make filing a bit easier for some taxpayers.

A Revised Form 1040

The 2018 IRS Form 1040 was a three-in-one consolidation of the Forms 1040, 1040-A and 1040-EZ. Tax year 2017 was the last year to use these three separate forms.

The tax return additionally underwent further tweaks and changes for the 2019 and 2020 tax years. These changes weren't as drastic, however. They just restructured some line numbers for entering income and deduction information.

It's unlikely that you'll notice these changes if you electronically file your tax return because tax-preparation software simply guides you through prompts to enter your information. It will take care of entering it onto the proper lines for you.

Calendar Year Vs. Fiscal Year

Both a calendar year and a fiscal year are comprised of a 12-month accounting period. A calendar year ends on the last day of the year (Dec. 31), but a fiscal year can end on another date. Companies can choose the 12-month accounting period that works best for them – this is their fiscal year – regardless of whether this period coincides with the calendar year.

This is significant when you're considering tax return deadlines because fiscal-year taxpayers have different filing deadlines if their year ends on a date other than Dec. 31. As a rule of thumb, fiscal-year tax returns are due on or before the ​fifteenth day of the fourth month​ after the end of an entity's fiscal year. The filing deadline shifts to the next business day when a fiscal-year due date falls on a weekend or a federal holiday. Filing on time is important.

Tax Return Filing Deadlines

To ensure your tax return meets its filing deadline, the IRS specifically defines what it considers to be "filed on time." A paper tax return must be properly addressed, with sufficient postage, postmarked and mailed by the due date. For example, it must be mailed and postmarked no later than April 15. if you're filing a Form 1040 with a due date of April 15.


  • You must electronically transmit the return by the due date according to the date and time in the time zone from which it's being sent if you e-file your tax return. Your return is late if you live in Georgia and you transmit it at 12:01 a.m. on April 16, even though it's only 9:01 p.m. on April 15 in California at that moment.

Certain military personnel may have extended tax filing guidelines, notably those who served or are currently serving in a combat zone or contingency operation, or those who are hospitalized as a result of an injury they received in these two circumstances. IRS Publication 3, the Armed Forces' Tax Guide, indicates that these service members have ​180 days​ to file a return and pay income tax after leaving a combat zone or contingency operation.

This publication gives additional guidelines for qualifying service members who can receive up to one year to file a return and pay income tax.

1040 Individual Tax Returns

The term “individual” for Form 1040 doesn’t imply that the taxpayer is filing as a single person. You can have a filing status of married, separated, head of household, widow(er) or single to file an individual tax return. This term simply differentiates individuals from entities such as corporations, business partnerships, trusts and estates.

  • Form 1040 filing deadline: ​April 15, 2021

Living and Working Outside the U.S.

United States citizens and resident aliens who are living and working outside the U.S. or Puerto Rico, as well as active military personnel, can file their 1040 returns later than the April 15 due date.

  • Form 1040 filing deadline for taxpayers living and working abroad: ​June 15, 2021

Combat zone participants may be able to extend their filing dates beyond June 15.

Estimated Tax Payment Deadlines

Self-employed calendar-year taxpayers must make quarterly estimated tax payments on IRS Form 1040-ES, "Estimated Tax for Individuals." Form 1040-ES quarterly filing deadlines are:

  • Jan. 15, 2021​ (for 4th quarter 2020)
  • April 15, 2021​ (for 1st quarter 2021)
  • June 15, 2021​ (for 2nd quarter 2021)
  • Sept. 15, 2021​ (for 3rd quarter 2021)
  • Jan. 15, 2021​ (for 4th quarter 2021)

Corporate Tax Return Deadline

Incorporated businesses, including C corporations but ​not​ S corporations, are required to file IRS Form 1120, the U.S. Corporation Income Tax Return, for calendar-year returns or the first yearly installment of estimated income.

  • Form 1120 filing deadline: ​April 15, 2021

S Corporations Tax Return Deadline

Businesses that are legally established as S corporations are required to file IRS Form 1120-S, the U.S. Income Tax Return for an S Corporation, for calendar-year returns.

  • Form 1120-S filing deadline: ​March 15, 2021

Partnership Tax Return Deadline

Businesses established as partnerships are required to file IRS Form 1065, the U.S. Return of Partnership Income.

  • Form 1065 filing deadline: ​March 15, 2021

Estates Tax Return Deadline

Executors of estates must file IRS Form 706, the United States Estate [and Generation-Skipping Transfer] Tax Return, for tax year 2020 for gross estates that total more than ​$11.58 million.​ This threshold is adjusted for tax-exempt gift exclusions and any applicable exemptions, and it's indexed for inflation so it can increase annually.

Trusts and Estates Tax Deadline

Fiduciaries of U.S. decedent's estate, trust or bankruptcy estate must file IRS Form 1041 (U.S. Income Tax Return for Estates and Trusts) to report estate-generated income, including gains and losses, and employment taxes paid to household staff.

  • Form 1041 calendar-year filing deadline: ​April 15, 2021

Gift Tax Return Deadline

Individual taxpayers who made a gift of ​more than $15,000​ to any one recipient in calendar year 2020 must file IRS Form 709, the United States Gift [and Generation-Skipping Transfer] Tax Return.

  • Form 709 filing deadline: ​April 15, 2021

Tax-Exempt Organizations Tax Return Deadlines

Tax-exempt organizations, charitable trusts and Section 527 political organizations must typically file annual information returns (Form 990 Series) to report transactions under IRS Code Section 6033.

  • Form 990 Series calendar-year filing deadline: ​May 15, 2021
  • Form 990 Series fiscal-year filing deadline: By the ​15th day​ of the ​fifth month​ after the end of the organization's accounting period

1040 Tax Extension Deadlines

Taxpayers who run into a little difficulty meeting 1040 tax filing deadlines can apply for an automatic extension to file.


  • Filing an extension allows taxpayers to ​file​ a late tax return without penalty, but it doesn't give them additional time to ​pay​ their tax. That's still due on April 15 and late payments will incur penalties.

Taxpayers can receive an automatic six-month extension to file their returns – to ​Oct. 15​ instead of ​April 15​ – by filing IRS Form 4868, the Application for Automatic Extension of Time to File U.S. Individual Income Tax Return. You can find Form 4868 by visiting and searching for it by number. You must typically include your tax payment when you file for the extension.

  • Form 4868 calendar-year filing deadline: ​April 15, 2021

Non-1040 Tax Extension Deadlines

Taxpayers who file tax returns other than the 1040 can have different filing extension deadlines that they should request on different extension forms. For example, you can request an automatic extension of ​5 and 1/2 months​ on Form 7004 if you must file a trust and estate tax return on Form 1041.

You can request an automatic extension of seven months if your fiscal year ends on ​June 30​ and and you're filing a C-corporation tax return. Check the instructions for your specific tax form to find the extension guidelines and the specific form to request your extension.

Late-Filing and Late-Payment Penalties

You’re looking at a potential three-fold penalty if you fail to file your tax return or request an extension by its due date or by its tax extension deadline:

  • Late-filing penalty:​ This ​5 percent​ penalty is calculated each month or part of a month on the unpaid taxes you owe, up to five months. If you file more than ​60 days​ past the due date, your penalty is either ​$435​ or ​100 percent​ of the taxes you owe, whichever is less. A failure-to-file penalty is reduced by the amount of a failure-to-pay penalty during any month that both penalties apply.
  • Late-payment penalty:​ You’ll still owe a late-payment penalty if you don't pay your taxes owed when you file for an extension, even if you request an extension by the filing deadline. This penalty is assessed monthly and calculated at ​0.5 percent​ of the tax you owe on the unpaid balance of your total tax bill.
  • Interest penalty:​ Your unpaid tax balance begins accruing interest, which is compounded daily, beginning one day after the filing deadline. The IRS calculates this interest rate as ​3 percent​ added to whatever the current federal short-term rate is at the time.

Reasonable Cause Penalty Relief

The IRS might be willing to work with you on a case-by-case basis if you find yourself unable to pay your tax debt. It depends on what's causing your inability to pay. The IRS might offer you penalty relief if it deems that you have “reasonable cause” and “sound reasons” for your financial dilemma. Among other examples, “sound reasons” include your inability to obtain necessary tax records, serious illness or natural disasters.

State Tax Return E-File Update

The IRS and states have jointly ruled that taxpayers cannot e-file their state tax returns without also filing their federal tax returns. You can use tax-preparation software to prepare your state return ahead of time, but you won't be able to actually transmit it unless you've already e-filed your federal return or if you transmit the two returns simultaneously.

You can electronically transmit your federal tax return regardless of whether you also e-file your state return, however.