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A misconception sends more nuclear decommissioning returns sideways than any line item: the assumption that fund income gets the 21% regular corporate rate. It does not. The fund's modified gross income on line 12 is taxed at a flat 20% rate, computed on line 13a, and missing that single fact reshapes everything downstream.
Form 1120‑ND is the Return for Nuclear Decommissioning Funds under IRC Section 468A, and the parts that catch teams are the related‑person rules in Part II. An act of self‑dealing carries a Section 4951 initial tax of 10% of the amount involved for a disqualified person and 2.5% for a participating trustee. Calendar‑year funds file by April 15, with a 6‑month extension available via Form 7004.
Key Takeaways
- Form 1120-ND is the annual income tax return for qualified nuclear decommissioning funds (NDFs) under IRC Section 468A and for certain related persons who receive amounts from or earn income through those funds.
- The fund is treated as a separate taxable entity. Its modified gross income (interest, dividends, and capital gains, less the allowed fund deductions and NOL) is taxed at a flat 20% rate on line 13a, not the 21% regular corporate rate.
- Utility companies and nuclear operators can deduct contributions to a qualified NDF in the year the contributions are made, subject to limitations tied to the NRC-approved decommissioning funding schedule.
- The fund’s assets may only be used for nuclear decommissioning costs – using fund assets for any other purpose disqualifies the fund from Section 468A treatment.
- Form 1120-ND is due April 15 for calendar-year funds, with a 6-month extension available via Form 7004. The fund’s tax year is typically the calendar year.
- Quick rule you can copy into your SOP: coordinate with the utility company’s nuclear compliance team early in Q4 to obtain the NRC-certified decommissioning cost estimate and funding schedule before year-end. These figures drive the allowable contribution deduction.
What Form 1120-ND Is and When to Use It
Form 1120-ND (Return for Nuclear Decommissioning Funds and Certain Related Persons) is the federal income tax return filed by qualified nuclear decommissioning funds established under IRC Section 468A. It is also filed by “related persons” – typically the nuclear power plant operator – who are required to report income attributable to amounts transferred from or earned by a qualified NDF that become taxable at the operator level under certain disqualification events.
The form exists because nuclear decommissioning funds occupy a unique position in the tax code: they are separate taxable entities (not treated as integral parts of the utility), their income is taxed annually, and the contributions made to them by nuclear operators are deductible within IRS-approved limits. Congress designed Section 468A to encourage utilities to set aside decommissioning funds proactively rather than waiting until plants are decommissioned – a process that can cost hundreds of millions of dollars per reactor.
Who Files Form 1120-ND
The trustee of a qualified NDF files Form 1120-ND on behalf of the fund each year to report the fund’s taxable income and pay the applicable tax. In addition, any “related person” as defined under Section 468A who receives amounts from, or is taxed on income earned by, the fund files a separate Form 1120-ND for their portion of the tax. In practice, the nuclear plant operator and the fund’s trustee coordinate closely to ensure both returns are consistent and accurate.
The Specialized Nature of This Return
Form 1120-ND is not a general corporate income tax return. It does not follow the standard Form 1120 structure for computing taxable income from business operations. Instead, it focuses on the fund’s investment portfolio income, the allowable tax deductions, and the applicable tax rate. Practitioners who encounter it for the first time should read the current IRS instructions and Treas. Reg. §1.468A closely before attempting to prepare the return.
What Is a Qualified Nuclear Decommissioning Fund?
Under IRC Section 468A, a qualified nuclear decommissioning fund must meet all of the following requirements:
- It must be a trust established and maintained in the United States in connection with a nuclear power plant licensed by the Nuclear Regulatory Commission (NRC).
- The assets of the fund must be held exclusively for decommissioning the nuclear facility and for paying reasonable administrative costs of the fund.
- Contributions to the fund must be made in accordance with a schedule of decommissioning costs approved by the NRC or appropriate state regulatory authority.
- The fund must be under the management of an independent trustee (not the nuclear plant operator).
- The fund must file an election under Section 468A to be treated as a qualified NDF for tax purposes.
Types of Entities That May Maintain NDFs
Qualified NDFs are primarily established by investor-owned electric utilities that operate commercial nuclear power reactors. Some publicly owned utilities and rural electric cooperatives also operate nuclear facilities and may maintain Section 468A funds. The fund structure is not available for research reactors or non-commercial nuclear facilities – only commercial power plants licensed under the Atomic Energy Act are eligible.
State-Regulated Decommissioning Funds
Some states require utilities to fund decommissioning through state-regulated mechanisms that do not qualify under Section 468A. These state-required funds are not eligible for the federal income tax deduction for contributions and are not required to file Form 1120-ND. The distinction between a Section 468A qualified fund and a state-mandated non-qualifying fund is important for both contribution deductibility and the Form 1120-ND filing obligation.
Section 468A Election and Contribution Deductions
A nuclear operator deducts contributions to a qualified NDF in the year the contributions are made, subject to an annual limit established by IRS-approved funding schedules. The Section 468A election must be made on or before the due date (including extensions) of the nuclear operator’s tax return for the first year contributions are made to the fund.
The Ruling Amount
Each year, the nuclear operator can obtain a “ruling amount” from the IRS that represents the maximum deductible contribution for that year. The ruling amount is based on the NRC-certified schedule of decommissioning costs, the fund’s current balance, and actuarial assumptions about future costs. Contributions in excess of the ruling amount are not currently deductible and must be returned to the operator or carried forward under specific rules.
Electing Not to Use a Ruling Amount
If an operator does not obtain a ruling amount, they can still make deductible contributions, but the deduction is limited to the lesser of the amount contributed or the amount that would have been allowed under the NRC schedule. Operators who skip the ruling amount process often find their deductions scrutinized during audit. My recommendation is always to obtain the ruling amount – it provides a clear, IRS-approved safe harbor for the deduction.
How to Complete Form 1120-ND
Part I – Fund Income
| Line | Description | Practitioner Note |
|---|---|---|
| 1 | Interest income | From fund investment portfolio; includes bond interest, CD interest, and similar |
| 2 | Dividends | From equities held in the fund; report gross dividends before DRD (fund does not receive DRD) |
| 3 | Capital gains | Net capital gains from fund investment activity; capital losses offset gains. Attach Schedule D (Form 1120) to support any capital gain net income reported |
| 4 | Other income | Miscellaneous fund income; attach a schedule describing the income (required for any amount reported as other income) and document the source in workpapers |
| 5 | Total income | Sum of Lines 1 through 4 |
Part II – Deductions and Tax
| Line | Description | Practitioner Note |
|---|---|---|
| 6 | Administrative costs of the fund | Trustee fees, legal costs, investment management fees directly related to fund operations |
| 7 | Taxable income | Line 5 minus Line 6 |
| 8 | Fund income tax (flat 20% on line 13a) | Multiply modified gross income on line 12 by 20% (0.20); no graduated brackets and not the 21% regular corporate rate |
| 9 | Credits and estimated tax payments | Apply any allowable credits; most NDFs pay estimated taxes quarterly |
| 10 | Tax due or refund | Balance due with return or amount to be refunded |
Signature and Filing Requirements
Form 1120-ND must be signed by the trustee of the fund, and an unsigned return is treated by the IRS as not filed. If the fund has a corporate trustee, an authorized officer signs. The form is mailed to the IRS service center designated in the current instructions – typically the center that handles Form 1120 filings for the operator’s geographic region. Most NDFs are not large enough to trigger mandatory e-filing, but verify the current e-file threshold requirements in the instructions each year.
Deadlines, Penalties, and Filing Requirements
| Item | Detail |
|---|---|
| Due date (calendar year) | April 15 (15th day of 4th month after tax year-end) |
| Extension | Form 7004 – automatic 6-month extension to October 15 (extends the time to file only, not the time to pay; the fund must still deposit the expected tax by the original due date, or interest under section 6601 and the failure-to-pay penalty accrue from that date) |
| Tax rate | Flat 20% on modified gross income (line 13a) – no graduated brackets, not the 21% corporate rate |
| Estimated tax | Fund pays quarterly estimated taxes if expected tax ≥ $500 |
| Failure-to-file penalty | 5% of unpaid tax per month, up to 25% |
| Failure-to-pay penalty | 0.5% of unpaid tax per month |
| Related person filing | Separate Form 1120-ND filed by related person if applicable; same due dates apply |
Quarterly estimated taxes are required when the fund’s expected annual tax liability is $500 or more. Use Form 1120-W (Estimated Tax for Corporations) as a worksheet to calculate the quarterly payment amounts. Payment vouchers depend on the fund’s EIN and the applicable due dates (April 15, June 15, September 15, and December 15 for calendar-year funds).
How NDF Income Is Taxed
The qualified NDF is treated as a separate taxable entity – not as a trust component of the nuclear operator’s consolidated return or as a grantor trust. All investment income earned by the fund (interest, dividends, capital gains) is taxable in the year earned, regardless of whether the fund distributes any of it. This is different from many trust structures where income passes through to beneficiaries.
The Flat 20% Fund Tax Rate
Form 1120-ND does not use graduated brackets. The fund computes modified gross income on line 12, then on line 13a the instructions direct you to “Multiply line 12 by 20% (0.20).” That single flat 20% rate applies to essentially all of the fund’s taxable income, regardless of size. It is not the 21% regular corporate rate from IRC Section 11(b), and it is not the estate and trust rate schedule under Section 1(e) – mixing those up is one of the most common errors we see on these returns.
Capital Gains Treatment
Net capital gains within the NDF do not get a separate preferential rate. Capital gain net income flows into the same modified gross income base and is taxed at the flat 20% on line 13a, the same as interest and dividends. You must attach Schedule D (Form 1120) to support any capital gain net income reported on line 2, so fund managers should still coordinate with tax counsel on portfolio turnover decisions and document the supporting schedule.
Related Person Rules and Form 1120-ND
A “related person” under Section 468A is typically the nuclear plant operator or an entity related to the operator. Related persons may be required to file Form 1120-ND if they receive amounts from the fund that are taxable to them – such as when the fund is disqualified or when the operator withdraws funds for non-decommissioning purposes.
Fund Disqualification
If a qualified NDF loses its qualified status – because assets were used for non-decommissioning purposes, or because the fund failed to comply with NRC requirements – the fund’s accumulated earnings become taxable to the related person (the operator) in the year of disqualification. This can create a substantial one-time tax hit. Related persons file Form 1120-ND to report and pay this tax.
Decommissioning Payments
When the plant is actually decommissioned and fund assets are drawn down to pay decommissioning contractors, those distributions are technically includible in the electing taxpayer’s income under section 468A(c)(1), though they are generally offset by a corresponding deduction for the qualifying decommissioning costs paid, so the net effect is no tax rather than a true exemption from tax. Only improper withdrawals or disqualification events create taxable income for related persons.
NRC Schedules and IRS Funding Requirements
The Nuclear Regulatory Commission requires all licensed commercial reactor operators to maintain a decommissioning funding plan (DFP) and report annually on the financial assurance status of their decommissioning funds. The NRC’s required funding levels, based on site-specific decommissioning cost estimates, directly inform the IRS’s ruling amount calculations for Section 468A purposes.
Coordinating with the NRC Funding Schedule
Each year, the nuclear operator updates its decommissioning cost estimate, adjusting for inflation, regulatory changes, and site-specific developments. These updated estimates affect the IRS ruling amount for deductible contributions. If the NRC approves a significant increase in the decommissioning cost estimate, the ruling amount for that year may increase, allowing a larger tax-deductible contribution to the NDF. Coordinate the NRC filing schedule with the tax filing calendar to capture any mid-year cost estimate changes in the current-year ruling amount request.
Plant License Extensions
When a nuclear plant receives an NRC license extension – operating for 20 additional years beyond the original license term – the decommissioning funding schedule shifts significantly. The fund has more time to accumulate assets before decommissioning, which changes the annual ruling amount calculation. Confirm with the IRS that the ruling amount request reflects the extended license schedule, not the original termination date.
Common Mistakes That Slow Things Down
Form 1120-ND looks deceptively short, but the same handful of errors surface every filing cycle, and each one invites correspondence from the IRS. Here is what my team catches most often.
Practical Checklists You Can Reuse
These checklists are copy-paste ready for your firm's SOP library. Lift them into your workpaper templates and adapt the line references to the fund's facts.
Pre-file fund return review
- Confirm the Section 468A election is on file and the fund still meets the qualified-fund requirements.
- Reconcile gross income on line 4 to lines 1 through 3 (taxable interest, capital gain net income, other income).
- Attach Schedule D (Form 1120) for any capital gain net income on line 2.
- Attach a supporting schedule for any amount on line 3 (other income) and line 8 (other deductions).
- Limit Part I deductions to the four allowed categories: trustees fees (line 5), taxes (line 6), accounting and legal (line 7), and other with schedule (line 8).
- Apply the flat 20% rate on line 13a to modified gross income on line 12.
- Complete Schedule L and confirm line 9 equals line 6.
- Disclose the ruling amount on Schedule M line 2b and compare it to contributions on line 2a.
- Confirm the officer signature and the paid-preparer PTIN are present.
Section 4951 self-dealing scan
- Review the year for any of the five self-dealing acts: sale or lease of property; lending or borrowing; furnishing goods, services, or facilities; payment of compensation; or use of fund assets by a disqualified person.
- If an act occurred, compute the initial tax in Part II: 10% of the amount involved for the disqualified person and 2.5% for a participating trustee.
- Keep the Section 4951 tax out of Part I and pay it in full with the return.
- Attach a schedule listing each act, its date, and the name, address, and identifying number of every disqualified person and trustee involved.
- Make the Section 4951 payment by check or money order payable to United States Treasury.
- Document any corrective action on Schedule M and note that correction does not erase the initial tax.
Extension and payment control
- Estimate the fund's expected tax before the original due date.
- Deposit the expected tax by the original due date even when filing Form 7004.
- Record the Form 7004 deposit on line 14e.
- Enter current-year estimated payments on line 14b and any prior-year overpayment credit on line 14a.
- Subtract any Form 4466 quick-refund amount on line 14c rather than adding it.
- Attach Form 2220 and complete line 15 if the fund underpaid estimated tax.
Keep 1120-ND Season From Stalling
Form 1120-ND is a low-volume, high-consequence return. A fund may file only once a year, but the work behind it stretches across the NRC-certified decommissioning schedule, the Section 468A ruling amount, the fund's full investment income on lines 1 through 4, and a Schedule L that has to tie out to the penny. A late or incomplete filing is not cheap either: the failure-to-file penalty runs 5% of unpaid tax per month up to 25%, with a minimum of the lesser of $510 or 100% of the tax for returns more than 60 days late in 2025, per the Form 1120-ND instructions and Rev. Proc. 2024-40.
The stall almost always comes from inputs arriving late, not from the math itself. When the ruling amount, the trustee's year-end statements, and the Schedule D detail all land in the final week, review gets compressed and errors slip through. The fix is to pull the recurring pieces forward and standardize how they enter the workpapers.
- Request the Section 468A ruling amount early and reconcile it to Schedule M line 2b against actual contributions on line 2a.
- Build a standing tie-out between the trustee's year-end statements and Schedule L so line 9 equals line 6 before review.
- Stage the investment income detail for lines 1 through 3 and attach Schedule D (Form 1120) the moment line 2 carries a capital gain.
- Run a Section 4951 self-dealing scan during fieldwork, not at signature, so any Part II tax is computed and funded on time.
- Confirm the Form 7004 deposit is recorded on line 14e and the flat 20% rate is applied on line 13a.
None of this requires more senior hours; it requires a disciplined intake and a documented review path. That is the model we run at Accountably: structured workpapers, multi-layer review, and turnaround SLAs that keep specialized returns like this one moving. See how our tax preparation and review services handle the production work so your reviewers stay on the judgment calls.
FAQs
What is Form 1120-ND used for?
Form 1120-ND is the annual income tax return for qualified nuclear decommissioning funds under IRC Section 468A. It reports the fund’s investment income (interest, dividends, capital gains), allowable deductions for fund administrative costs, and computes the fund income tax at a flat 20% rate on modified gross income (line 13a). It is also filed by related persons (typically nuclear plant operators) if they receive taxable amounts attributable to the fund.
Who must file Form 1120-ND?
Qualified nuclear decommissioning funds that have made a Section 468A election must file Form 1120-ND each year they have taxable income. The fund’s trustee signs and files the return. Related persons who are taxable on amounts from the fund – such as when the fund loses qualified status or when amounts are improperly withdrawn – also file Form 1120-ND for their portion of the tax.
What tax rate applies to nuclear decommissioning fund income?
Form 1120-ND applies a flat 20% rate to the fund’s modified gross income on line 13a (“Multiply line 12 by 20% (0.20)”). There are no graduated brackets, and it is not the 21% regular corporate rate. Capital gain net income flows into the same modified gross income base and is taxed at the same flat 20% rate, with a Schedule D (Form 1120) attached to support any capital gain on line 2.
When is Form 1120-ND due?
For calendar-year funds, Form 1120-ND is due April 15. Fiscal-year funds file by the 15th day of the fourth month after their fiscal year-end. An automatic 6-month extension is available by filing Form 7004 by the original due date. Quarterly estimated tax payments are required when expected annual tax is $500 or more.
What is a qualified nuclear decommissioning fund under Section 468A?
A qualified NDF is a trust established in connection with a commercial nuclear power plant licensed by the NRC, held exclusively for decommissioning the facility, managed by an independent trustee, and funded according to an NRC-approved decommissioning cost schedule. The nuclear operator makes a one-time election under Section 468A to treat the fund as qualified, enabling annual deductible contributions within IRS-approved limits called “ruling amounts.”