Tax
Form 1120-S (S-Corporation Return)
The IRS form filed by S-corporations to report income, deductions, and allocations to shareholders.
Like the 1065 for partnerships, Form 1120-S is an informational return. S-corp income flows through to shareholders via Schedule K-1.
Due March 15 (calendar-year S-corps). Form 7004 grants a 6-month extension to September 15.
An S-corp election (Form 2553) is required before filing 1120-S. Late or missing elections can be remedied via Rev. Proc. 2013-30 in many cases, but only if discovered.
Common pitfalls
- Filing a 1120-S without a valid S-corp election in place; the return gets rejected or treated as a C-corp
- Owner-employees not running payroll; the IRS reclassifies distributions as wages and hits the owner with back payroll tax + penalties
- Single class of stock violations: voting differences are fine, but preferred returns or differential rights kill the S-corp election
Related service
See tax and CPA servicesRelated guides
Have a Form 1120-S (S-Corporation Return) situation in your business?
Federal, state, and local returns prepared and reviewed by a licensed CPA, with the planning done before year-end rather than after it.