Oil Spill Tax Expired: IRS Nos. 18 and 21
If you report petroleum tax, the oil spill tax on Form 720 changed on January 1, 2026. The two oil spill taxes, IRS Nos. 18 and 21, expired after 2025. Part of what you used to pay per barrel is gone, but the petroleum Superfund tax remains, so you are still a Form 720 Superfund filer.
The Instructions for Form 720 (Rev. June 2026) carry this caution:
The Instructions for Form 6627 (Rev. January 2026) repeat that caution almost word for word.
What expired, and what didn't?
| Tax | IRS No. | Status for 2026 | Rate |
|---|---|---|---|
| Domestic petroleum oil spill tax (crude oil received) | 18 | Expired after 2025 | Was $0.09 per barrel |
| Imported petroleum oil spill tax (products entered) | 21 | Expired after 2025 | Was $0.09 per barrel |
| Domestic petroleum Superfund tax | 53 | In effect | $0.18 per barrel |
| Imported petroleum products Superfund tax | 16 | In effect | $0.18 per barrel |
Before 2026, the petroleum tax rate was two taxes added together: the Superfund financing rate and the $0.09 Oil Spill Liability Trust Fund rate. For 2026, the Form 6627 instructions state the rate as the Superfund financing rate only. The other environmental lines, such as those for chemicals and ozone-depleting chemicals, weren't part of this expiration.
The June 2026 Form 720 itself shows "Reserved for future use" where lines 18 and 21 used to be. The instructions still refer to "the lines for IRS Nos. 18 and 21," and the IRS e-file business rules for 2026Q4 still include checks on those two tax amounts. So the IRS has kept room for them in case of an extension. Don't read that as a duty to report.
What should you do on a 2026 return?
- Check for an extension first. Before filing, look at IRS.gov/Form6627. That is the IRS page named in the caution.
- Report nothing for Nos. 18 and 21, unless that page shows an extension that covers your period.
- Use the January 2026 revision of Form 6627. The Form 6627 instructions say filers should use it for 2026.
- Report the Superfund tax as usual. Domestic crude oil goes on IRS No. 53, and imported petroleum products go on IRS No. 16, at $0.18 per barrel.
- Remove any old templates. A worksheet or system built for 2025 may still add the extra $0.09.
What does a 2026 calculation look like now?
The refinery and figures are made up. A refinery operator receives 250,000 barrels of domestic crude oil in a 2026 quarter.
- Superfund tax on IRS No. 53: 250,000 x $0.18 = $45,000.
- Oil spill tax on IRS No. 18: nothing to enter, unless the tax is extended.
The liable parties don't change. Publication 510 and the Form 6627 instructions say the refinery operator is liable for tax on crude oil received at a U.S. refinery. The person entering a petroleum product into the country is liable for the tax on that product. A person using domestic crude oil before it reaches a U.S. refinery is liable as the user, with a stated exception for extraction on the premises.
The IRS caution also says the section 4611 tax on exported crude oil currently doesn't apply, following its acquiescence in a court case (AOD 2023-01). That point is separate from the oil spill expiration.
What about barrels from 2025, and earlier returns?
The IRS says the tax expired after 2025, and the Form 6627 instructions give the date as December 31, 2025. Crude oil received or products entered on or before that date were still subject to it, on the return for that period. If you need to correct a return you already filed, the instructions direct you to Form 720-X rather than an adjustment on a later Form 720. Our Form 720-X guide explains how that works.
What if Congress extends the taxes?
Our sources don't say what an extension would look like, so nobody should assume its rate or its start date in advance. The IRS points to IRS.gov/Form6627 as the place to learn about it. Publication 510 also says the $0.09 rate doesn't apply after December 31, 2025, "unless the tax gets extended." Checking that page each quarter takes a minute and protects your filing either way.
Filing your 2026 Form 720
Once you know your barrels, EasyFile720 offers guided Form 720 filing online from business details through submission. It covers Part I categories, the rates for the return are built in, and validations catch common mistakes before you submit. You pay $39.95 when you file, and creating an account is free. For the other taxes on this part of the return, see our Superfund and chemical tax page.
FAQ
Do I still attach Form 6627?▼
Yes, for the petroleum Superfund tax. Form 720 says to attach Form 6627 for environmental taxes, and the Form 6627 instructions say to use the January 2026 revision.
Has Congress extended the oil spill tax?▼
The IRS documents we checked say the tax expired and don't report an extension, but they carry their own publication dates. The IRS directs filers to IRS.gov/Form6627 to find out, so check there before each 2026 return.
What if I already included oil spill tax on a 2026 return?▼
The instructions say adjustments to liabilities reported for prior quarters go on Form 720-X, not on a later Form 720. Check that return and read the Form 720-X rules for your situation.
File Form 720 online
Create a free account with no credit card and build your return. You pay $39.95 only when you file. EasyFile720 is an IRS-authorized e-file provider, and you get an acknowledgment when the IRS accepts your return.
Sources: Instructions for Form 720 (Rev. June 2026); Form 720 (Rev. June 2026); Instructions for Form 6627 (Rev. January 2026); IRS Publication 510 (Rev. December 2025); IRS Form 720 Business Rules 2026Q4v1.0. General information, not tax advice. Confirm how the rules apply to you with a qualified advisor or the IRS.
