Form 1139, Corporation Application for Tentative Refund, is how a C corporation asks for a quick refund of tax paid in earlier years by carrying back a net operating loss, a net capital loss or an unused general business credit. It's generally due within 12 months of the end of the tax year the loss or credit arose, and the IRS processes it within 90 days. Since 2021, ordinary operating losses can't be carried back; only farming losses and losses of non-life insurance companies can.
Everything below comes from the IRS's Form 1139 and its instructions, both Rev. December 2025, as of October 2026. The IRS says to use this revision for 2025 and later years until a new one is issued.
What Form 1139 can get you a refund for
A corporation, other than an S corporation, files Form 1139 for a quick refund from any of these:
- the carryback of a net operating loss (NOL)
- the carryback of a net capital loss
- the carryback of an unused general business credit
- an overpayment of tax from a claim of right adjustment under section 1341(b)(1)
- an election under section 53(e)(5) to claim 100% of prior year minimum tax for a tax year beginning in 2018
Tax-exempt organizations claiming back tax reported on Form 990-T don't use this form; their own instructions explain the route.
How far back each item can go
| Item | Carryback period | What happens to the rest |
|---|---|---|
| NOL from a farming loss (tax years beginning after 2020) | 2 years | Carried forward indefinitely, subject to limits |
| NOL of an insurance company other than life insurance | 2 years | Carried forward 20 years |
| Any other NOL from tax years beginning after 2020 | No carryback | Carried forward only |
| NOL from tax years beginning after 2017 and before 2021 | 5 years | Carried forward indefinitely |
| Net capital loss | Generally 3 years | Carried forward under the capital loss rules |
| Unused general business credit | 1 year | Refigured on Form 3800 for the carryback year |
This table is the insight most owners miss. Form 1139 still exists and still gets used, but for an ordinary trading company with a loss in 2025, there's usually no NOL carryback to claim. The quick refund now mostly comes from capital losses, business credits and the two special loss types.
The 12-month deadline
Generally, file within 12 months of the end of the tax year in which the NOL, capital loss, unused credit or claim of right adjustment arose. Two conditions apply at the same time:
- the corporation must have filed its income tax return for that year no later than the day it files Form 1139
- Form 1139 is filed separately, with the IRS Service Center where the corporation files its return, never inside the return itself
If the corporation used Form 1138 to get more time to pay because it expected an NOL carryback, filing Form 1139 by the last day of the month that includes the return's due date, with extensions, extends that time to pay further.
What to attach
- The first two pages of the corporation's Form 1120 for the loss or credit year.
- The forms and schedules that create the carryback, such as Schedule D (Form 1120) or Form 3800.
- All Forms 8886 filed with that return, plus any election statements.
- Every carryback year form and schedule that had to be refigured.
- Form 2848 if you want the IRS to deal with a representative.
Corporations can now e-file Form 1139 using the new Form 8453-TR. A new line 2d is for resubmitting the form after IRS correspondence, with a copy of that letter attached.
The 90-day review and what it isn't
The IRS processes the application within 90 days of the later of the date you file a complete Form 1139 or the last day of the month that includes the loss year's return due date, with extensions. A paid refund doesn't mean the IRS has accepted the figures. If it later finds overstatement, negligence or a substantial understatement, penalties under section 6662 can follow, with interest on anything refunded in error, and an excessive refund can be billed as if it were a math error.
The form can also be disallowed for material omissions or math errors not fixed within the 90 days, and that decision can't be challenged in court. The fallback is a regular refund claim on Form 1120X.
Want AI doing the heavy lifting in your marketing?
I build the systems that handle the boring 80 percent, so you get your week back. Done properly, with the human kept in.
Form 1139 or Form 1120X?
| Use Form 1139 when | Use Form 1120X when |
|---|---|
| You want a fast, tentative refund within the 12-month window | You've missed the 12 months; Form 1120X is generally allowed within 3 years after the loss year's return was due |
| The carryback is an NOL, capital loss or general business credit | You're carrying an item other than an NOL to a section 965 year, or a foreign tax or business credit freed up by a loss carryback |
Waiving the carryback
A corporation with a farming or non-life insurance loss can choose to waive the entire carryback period and carry the loss forward only. It's made by checking the box on Form 1120, Schedule K, line 11, and filing the return on time. Once made, the election can't be undone, so decide before filing.
The verdict
Form 1139 is a cash flow tool: it turns a loss or unused credit into a refund within months rather than years. Check first whether your loss can be carried back at all, because since 2021 most can't. If it can, file the return, then Form 1139 separately, inside 12 months, with every attachment, and keep the numbers clean enough to survive a later review.
Frequently asked questions
What is Form 1139 used for?
A corporation, other than an S corporation, uses it to apply for a quick refund from carrying back an NOL, net capital loss or unused general business credit, or a claim of right adjustment.
When is Form 1139 due?
Generally within 12 months of the end of the tax year in which the NOL, net capital loss, unused credit or claim of right adjustment arose.
Can a corporation still carry back a net operating loss?
For losses in tax years beginning after 2020, only farming losses and losses of insurance companies other than life insurance companies can be carried back, for 2 years.
How long does the IRS take to process Form 1139?
The IRS processes it within 90 days of the later of the complete filing date or the last day of the month that includes the loss year's return due date, with extensions.
Can I file Form 1139 with the corporation's tax return?
No. File it separately with the IRS Service Center where the corporation files its return, or e-file it using Form 8453-TR.
What if Form 1139 is disallowed?
No court challenge is allowed, but the corporation can file a regular claim for refund on Form 1120X.
