No single deadline
An individual claiming a refund has three years from filing or two years from paying, whichever is later, and the IRS has a longer window to assess more tax.
The short answer
Partnerships file an AAR
Most partnerships cannot file an amended return at all. They file an administrative adjustment request instead.
90 days to tell NY
New York gives you 90 days to report a federal change. Miss it and New York can assess at any time.
Two clocks, not one
Two limits run on every filed return
There is no single deadline. It depends on the entity that filed, on whether you want money back or the IRS wants more, and on the state. For an individual claiming a refund it is three years from filing or two years from payment, whichever is later.
Two separate limits run on every filed return. One sets how long you have to claim money back. The other sets how long the IRS has to assess more tax. They are different lengths, and only the refund window closes for good.
00Two clocks
Refund window vs assessment window
Different lengths, and only one of them closes for good.
The refund clock
How long you have to claim money back.
3 years from filing or 2 years from payment, whichever is later. Once it closes, the refund is gone.
The assessment clock
How long the IRS has to assess more tax.
Longer than the refund clock, and in some cases it never closes at all.
01By entity type
The refund deadline by entity type
| Filer | Deadline to claim a refund | Form |
|---|---|---|
| Individual | 3 years from filing or 2 years from payment, whichever is later | 1040-X |
| C corporation | Same test, from the corporation's own dates | 1120-X |
| S corporation | Same test, from the corporation's own dates | 1120-S, amended box checked |
| Partnership under the BBA regime | 3 years from the later of the filing date or the unextended due date | 8082 with an amended 1065 |
| Partnership that elected out | Same test as an individual | 1065-X |
| Employer, payroll taxes | 3 years from filing or 2 years from payment | 941-X |
02Individuals
Individual refund deadline: three years from filing or two years from payment
Take the later date
Filing date
+3 yr
or
Payment date
+2 yr
To claim a refund you generally have three years from the date you filed, or two years from the date you paid the tax, whichever is later. Miss both and the refund is gone.
03Corporations
C corporation and S corporation correction deadlines
A corporation runs on the same three-year and two-year test as an individual, measured from its own filing and payment dates.
- C corporations correct a filed return on Form 1120-X. The refund window is three years from the date the Form 1120 was filed or two years from the date the tax was paid, whichever is later.
- S corporations file Form 1120-S with the amended return box checked, and must issue corrected Schedules K-1 to every shareholder.
- A loss carryback uses Form 1139 for a quick refund, which has to be filed within 12 months of the end of the loss year. Form 1120-X stays available on the normal window if you miss that.
Shareholder dates matter more than the corporate one. A corrected K-1 reaches a shareholder who may have filed two years ago, each on its own deadline. Check the shareholders’ dates before you file, not after.
04Partnerships
Partnership corrections and the administrative adjustment request
Most partnerships cannot file an amended return at all.
The centralized partnership audit regime has applied to partnership tax years beginning after 2017. Under it, a partnership corrects a filed return by filing an administrative adjustment request under Section 6227.
Deadline
3 years from the later of the filing date or the unextended due date. The request cannot be filed at all once the IRS has mailed a notice of administrative proceeding for that year.
The forms
An amended Form 1065 with Form 8082 when filing electronically, or Form 1065-X on paper.
No amended K-1s
Partners receive Form 8986 instead, and they pick the adjustment up on their current year return rather than by amending the old one. A partner cannot claim it as a refund on a Form 1040-X.
Who pays
The partnership pays an imputed underpayment computed at the highest rate, or elects to push the adjustment out to the reviewed-year partners on Forms 8985 and 8986.
Electing out
A partnership with 100 or fewer Schedules K-1, all issued to eligible partners, can elect out of the regime for the year on Schedule B-2 of Form 1065. A partnership or a trust among the partners disqualifies the election. It has to be made every year.
Whether the election was made, and whether it was valid, is the first question to answer. An invalid election out means the partnership has been filing amended returns that never counted.
Worked example
A calendar-year partnership filed its 2022 Form 1065 on Sep 15, 2023 under extension. The unextended due date was Mar 15, 2023. The deadline runs from the later of the two, so the request has to be filed by Sep 15, 2026.
05Superseding returns
Correcting a return before the due date
A return you file again before the due date replaces the first one completely. It is called a superseding return, and it is a better outcome than an amendment wherever it is still available.
Before the due date, extensions included
- ✓File a superseding return
- ✓It becomes the return of record
- ✓Elections stand as though made the first time
- ✓A partnership avoids the AAR
After the due date
- ✗Amendment rules take over
- ✗3 years from filing, or 2 from payment
- ✗Some elections can no longer be changed
- ✗A partnership files an administrative adjustment request
Say something as soon as you find the error. The route available before that date avoids the amendment rules.
06IRS deadlines
How long the IRS has to assess
Measured from the date you filed, not the tax year.
Nothing unusual
Section 6501(a)
3 years
Understated by more than 25 percent
Or over $5,000 from a foreign financial asset
6 years
Fraudulent return, or never filed
No period ever starts
No limit
Missing international information return
Forms 5471, 8938, 3520, 8865
No limit on the whole return
Section 6501(c)(8) holds the period open for everything on the return, not just the foreign item, until three years after the missing form goes in.
Consent to extend
The IRS can ask you to extend the assessment period on Form 872. You are not obliged to sign it, and the decision is worth taking advice on.
Once tax is assessed, a separate ten-year collection period runs.
A year you treat as closed can still be open to the IRS long after it closed to you. That is the practical reason not to sit on a known understatement.
07Exceptions
Exceptions that extend or shorten the refund window
Several rules in Section 6511 move the three-year and two-year deadline, and one caps what you can recover even when you file on time.
- A return filed early counts as filed on the due date. A 2025 return filed on February 1, 2026 starts its three years on April 15, 2026.
- The lookback caps the amount. File inside the three-year window and the refund cannot exceed the tax you paid in the three years before the claim. File on the two-year payment test and it cannot exceed the tax you paid in the two years before it. Withholding counts as paid on the due date.
- Seven years for a worthless security or a wholly worthless bad debt. Partial worthlessness gets the ordinary three years.
- Financial disability suspends the period. This covers a medical condition that stopped you managing your own affairs where nobody held authority to act for you. It needs a physician’s statement.
- Disaster relief moves the date. Where the IRS postpones a filing deadline for a declared disaster, the refund window moves with it.
- An accounting method change is not an amendment. Correcting a method used on two or more returns goes on Form 3115, and Form 3115 has no three-year limit.
08New York
New York deadlines and the 90 day federal change report
New York gives you three years from filing or two years from payment to claim a refund, the same test as the federal one. The obligation running in the other direction is much shorter.
The 90-day report timeline
Day 0
You file an amended federal return, or the IRS makes a final determination on yours.
≤ 90d
File the amended New York return. Form IT-201-X or IT-203-X for individuals, an amended Article 9-A return for corporations. 120 days on a combined corporate return.
> 90d
Where the federal change increases New York tax, New York can assess at any time. No limitation period runs in your favor.
So a federal correction is rarely one deadline. It is a federal one, a state one, and a reporting deadline that starts running from the date the federal change became final.
09Recordkeeping
How long to keep records for an open year
How long a year stays open is how long you should keep the paperwork for it.
| Situation | Keep records for |
|---|---|
| Return filed, nothing unusual | 3 years from the filing date |
| Gross income understated by more than 25 percent | 6 years |
| Employment tax records | 4 years from the due or payment date |
| Worthless security or bad debt claimed | 7 years |
| Property you own | 3 years after you sell it |
| International information return not filed | Until 3 years after you file it |
| No return filed | Permanently |
Scans are acceptable to the IRS.
10FAQ
Frequently asked questions
How long do I have to amend a tax return?
Three years from the date you filed or two years from the date you paid, whichever is later, for an individual claiming a refund. Corporations run on the same test from their own dates, and most partnerships file an administrative adjustment request rather than an amendment.
What happens if I miss the three year deadline?
The refund is gone. The IRS cannot pay a refund on a claim filed after the period closes, and there is no general hardship exception. You can still correct a return that increases tax, and doing it voluntarily is treated differently from waiting for the IRS to find it.
Can a partnership file an amended return?
Only if it validly elected out of the centralized regime for that year, or if it files a superseding return before the due date including extensions. Otherwise it files an administrative adjustment request.
How far back can the IRS audit me?
Three years normally, six years where gross income was understated by more than 25 percent, and with no limit where a return was fraudulent or was never filed. A missing international information return keeps the whole return open indefinitely. In collection practice the IRS focuses on the most recent six years, but that is policy rather than law. A New York State tax audit runs on its own three year period, which never starts at all where you failed to report a federal change.
Does amending a return restart the IRS clock?
Not generally. Filing Form 1040-X does not restart the three year assessment period. An amendment filed within 60 days of that period closing gives the IRS an extra 60 days, but only for the additional tax the amendment shows.
What if I never filed at all?
No limitation period ever starts, so the IRS can assess that year at any point.
Do I have to tell New York if I amend my federal return?
Yes, within 90 days. Missing that deadline lets New York assess the resulting tax at any time, with no limitation period protecting you.
Can I amend a return to change an election?
Sometimes. Some elections are irrevocable once made, some can still be made on a superseding return, and some need a private letter ruling to fix. Check the election itself before assuming an amended return will carry it.
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Whether your year is still open
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Reviewed by George Dimov, CPA, New York, NY. Serving clients in all 50 states, 15+ years as a tax accountant in New York City advising individuals and businesses on return corrections and IRS deadlines. President of George Dimov, CPA, a New York City firm serving clients across the five boroughs and nationwide.