Finding an error in a filed return is unpleasant, and common. The right response is not panic and not silence. It is a methodical correction, using the right form for your entity, that fixes the owners' returns too.
When you should amend
- Income was left out or reported incorrectly.
- Deductions or credits were missed, or claimed in error.
- Expenses were misclassified in a way that changes the result, such as personal costs deducted as business expenses.
- A K-1 was wrong, or an owner's share was reported incorrectly.
- A depreciation, basis, or inventory error was discovered.
- Payroll or information return amounts do not match the return.
When you may not need to amend
Minor math errors are often corrected by the IRS, and missing schedules or forms may be requested by notice. But do not rely on the IRS to catch errors in your favor or against you. If a mistake changes the tax, income, or an owner's reported figures, correct it.
The form depends on your entity
- Sole proprietors and single-member LLCs: Form 1040-X, along with corrected Schedule C and Schedule SE where needed.
- C corporations: Form 1120-X. The IRS says corporations use it to correct a Form 1120 or 1120-A as originally filed.
- S corporations: generally a corrected Form 1120-S filed with the amended return box checked, along with amended K-1s for shareholders.
- Partnerships and multi-member LLCs: generally a corrected Form 1065 with the amended return box checked and amended K-1s. Larger partnerships under the centralized partnership audit regime may use an administrative adjustment request instead. Confirm which regime applies to you.
Pass-through amendments ripple outward
A change on a partnership or S corporation return changes each owner's K-1, and each owner may then need to amend their personal return. Amend the entity first, send corrected K-1s, then amend the owners' returns. Coordinating this is where most of the effort lies. See multi-member LLC tax filing and S-corp tax return filing.
Time limits to watch
Refund claims generally have to be made within a limited period, commonly three years from the date the original return was filed or two years from the date the tax was paid, whichever is later. The IRS also has a limited window to assess additional tax. Because the timing rules depend on the filing date and any extensions, confirm the dates for the specific year before assuming a refund is still available.
Step-by-step process
- 1Identify exactly what is wrong, and quantify the effect on income, deductions, and tax.
- 2Correct the books first so the amended return is supported by clean records. See bookkeeping cleanup services.
- 3Prepare the corrected return on the form that fits your entity.
- 4Include an explanation of each change.
- 5Update related items: K-1s, state returns, payroll filings, and estimated payments.
- 6File, and keep proof of filing.
- 7Pay any additional tax and interest promptly, and consider whether penalty relief is available. See IRS penalty abatement help.
State returns follow
Most states require you to notify them when a federal change alters your state taxable income, and the deadline to do so varies by state. Check each state where you file. A federal amendment that is not mirrored at the state level can produce a mismatch notice later.
Amending vs. filing late returns
An amendment corrects a return you already filed. A late filing is a return that was never submitted. If you are missing returns entirely, start with unfiled business tax returns. If the underlying problem is an S election that was never valid, read late S-corp election relief.
Amending pass-through returns affects every owner and sometimes the entity's status. Have a qualified preparer review the facts, the form, and the filing method before you submit, especially for partnerships under the centralized audit regime.
Our tax preparation service handles amended entity and owner returns together. To schedule a consultation, tell us the tax year, entity type, and what needs correcting.
