IRS Authorized E-file Provider for Tax Extension Forms
IRS Authorized E-file Provider for Tax Extension Forms AICPA SOC Certified Company ExpressGuarantee

Form 1120-S An Overview:
Due Date, Extension, Mailing Address, and Penalties

IRS Authorized E-file Provider for Tax Extension Forms

IRS Form 1120-S, U.S. Income Tax Return for an
S Corporation

- Updated Feb 20, 2024 - 8.00 AM Admin, ExpressExtension

As a business owner in the U.S, you must file a business income tax return with the IRS each year.

If your organization elected as a S-corporations, you must file Form 1120-S. IRS requires
S-corporations to report the income, gains, losses, deductions, credits, etc., of a domestic corporation or other entity for any tax year covered by an election to be an S corporation.

What is Form 1120-S?

IRS Form 1120-S is a U.S. Income Tax Return for businesses registered as S corporations. The return reports the income, gains, losses, deductions, credits, etc., of S corporation shareholders to the IRS.

Along with the 1120-S return, the business should also include the Schedule K-1 form. This tells the IRS the percentage of company shares owned by each shareholder for the tax year. This must be prepared for every shareholder.

Who must file 1120-S?

A domestic corporation or other entity must file Form 1120-S if the following requirements are met:

  • The organization elected to be treated as an S corporation for that tax year by
    filing Form 2553,
  • The IRS accepted the election, and
  • The election remains in effect.

Please note, after filing Form 2553, the business should receive the confirmation that the filed Form 2553 was accepted. If the corporation has not received a notification of acceptance or nonacceptance of the election within 2 months of filing Form 2553
(5 months if you checked box Q1 to ask for a letter ruling), please follow up by calling

Do not file Form 1120-S for any tax year before the year the election takes effect.

When is the deadline to file 1120-S?

Generally, an S corporation with a fiscal year must file Form 1120-S by the 15th day of the 3rd month after the end of its tax year.

For calendar year corporations, this due date is March 15, 2024.

If the deadline falls on a Saturday, Sunday, or any legal holiday, the corporation can file on the following business day.

Filing an Extension for 1120-S

In case you are not able to prepare your 1120-S return to file by the regular due date, you can get an automatic six month extension of time to file the tax return by applying Form 7004, Application for Automatic Extension of Time To File Certain Business Income Tax, Information, and Other Returns, with the IRS.

By doing so, the S-corporation can extend the tax filing deadline until
September 15, 2024 without any explanation. Learn more about S-corporation tax extension.

Please note, the corporation must file Form 7004 on or before the regular deadline of
the 1120-S return.

How to File 1120-S Form?

S-corporations can file 1120-S either by paper or electronically.

You must electronically Form 1120-S, if the S-corporation has more than $10 million total assets to file or at least 250 returns a year.

Please note, the S Corporations can usually e-file Form 1120-S, related forms, schedules, statements, and attachments; Form 7004 (automatic extension of time to file); Forms 940, 941, and 944 (employment tax returns), Form 1099, W2 and other information returns.

Where to Mail 1120-S?

If you choose to paper file, then mail the corporation's return to the applicable IRS address listed below:

If the corporation's primary business, office, or agency is located in Total assets at the end of the tax year Address
Connecticut, Delaware, District of Columbia, Georgia, Illinois, Indiana, Kentucky, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, West Virginia, Wisconsin Less than $10 million and Schedule M-3 isn't filed Department of the Treasury
Internal Revenue Service
Center Kansas City,
MO 64999-0013
$10 million or more, or less than $10 million and Schedule M-3 is filed Department of the Treasury
Internal Revenue Service
Center Ogden,
UT 84201-0013
Alabama, Alaska, Arizona, Arkansas, California, Colorado, Florida, Hawaii, Idaho, Iowa, Kansas, Louisiana, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, Wyoming Any amount Department of the Treasury
Internal Revenue Service
Center Ogden,
UT 84201-0013
A foreign country or U.S. possession Any amount Internal Revenue Service
Center P.O. Box 409101 Ogden,
UT 84409

Penalties for late filing Form 1120-S

There are two penalties that apply to the 1120-S return:

  • Late Filing
  • Late Payment of Tax

Late filing penalty

The penalty is incurred if the return is filed after the regular or extended due date of the
return as follows:

  • For returns with no tax is due, the penalty is $210 for each month or part of a month (up to 12 months).
  • If the tax is due, the penalty is $210 plus 5% of the unpaid tax for each month or part of a month the return is late, up to a maximum of 25% of the unpaid tax.
  • The minimum penalty for a return that is more than 60 days late is the smaller of the tax due or $435.

Late Payment of Tax

A corporation that doesn't pay taxes by the original due date will be penalized 1/2 of 1% of the unpaid tax for each month or part of a month the tax is not paid, which can go up to a maximum of 25% of the unpaid tax.

Note: The penalty won't be imposed if the corporation has the reasonable cause for failure to pay on time.

Extend your 1120-S deadline by filing Form 7004 with ExpressExtension

S Corporations can file the extension Form 7004 by the original deadline of
March 15, 2024 to extend their Form 1120-S deadline up to 6 months. Failing to file the extension or original form by March 15, 2024 can lead to penalties.

E-filing your 1120-S extension with ExpressExtension is simple and easy. The application walks you through the process of applying for your extension step-by-step and you can complete your 7004 extension in minutes.

ExpressExtension also gives you the option to submit your tax payment along with Form 7004 to the IRS via

  • Electronic Funds Withdrawal (EFW)
  • Electronic Federal Tax Payment System (EFTPS)

Avoid further late filing penalties. File extension for your S-corp Now!

Apply Extension Now

See why our customers choose us year after year

ExpressExtension - The Smart Business Owners Choice

Express Extension Support

File extension for your 1120-S before deadline and extend your deadline up to 6 months