@sp1995 wrote:
......(indeed IRS website says that you supposedly have to e-file an amendment)........
Where?
Electronic Filing
S corporations can generally electronically file (e-file) Form 1120-S, related forms, schedules, statements, and attachments; Form 7004 (automatic extension of time to file); and Forms 940, 941, and 944 (employment tax returns). Form 1099 and other information returns can also be electronically filed. The option to e-file doesn't, however, apply to certain returns.
For returns filed on or after January 1, 2024, S corporations are required to e-file Form 1120-S if they file 10 or more returns of any type during the calendar year (including income tax, employment tax, excise tax, and information returns). See Regulations section 301.6037-2. However, these corporations can request a waiver of the electronic filing requirements.
Amended Return
To correct a previously filed Form 1120-S, file an amended Form 1120-S and check box H(4) on page 1. Attach a statement that identifies the line number of each amended item, the corrected amount or treatment of the item, and an explanation of the reasons for each change.
If the income, deductions, credits, or other information provided to any shareholder on Schedule K-1 or K-3 is incorrect, file an amended Schedule K-1 or K-3 (Form 1120-S) for that shareholder with the amended Form 1120-S. Also give a copy of the amended Schedule K-1 or K-3 to that shareholder. Check the “Amended K-1” or “Amended K-3” box at the top of the Schedule K-1 or K-3 to indicate that it is an amended Schedule K-1 or K-3.
A change to the corporation's federal return may affect its state return. This includes changes made as the result of an IRS examination. For more information, contact the state tax agency for the state(s) in which the corporation's return was filed.
https://www.irs.gov/instructions/i1120s#en_US_2024_publink11515kd0e1133
