How to Report an Inherited IRA Distribution on Your Tax Return
Every distribution you take from an inherited traditional IRA triggers a Form 1099-R — and the distribution code in Box 7 is what tells the IRS (and your tax software) that this is an inherited account, not your own.
What Form 1099-R is — and what it tells you
Your IRA custodian sends a Form 1099-R for every calendar year in which you took a distribution from the inherited account. If you took five separate distributions in the same year, you'll get one 1099-R aggregating them all — not five forms.
The form has several boxes that matter for inherited IRAs:
| Box | What it says | What to do with it |
|---|---|---|
| Box 1 | Gross distribution — the total amount distributed to you | Goes on Form 1040 Line 4a |
| Box 2a | Taxable amount — what the custodian believes is taxable. Often left blank for inherited IRAs. | Goes on Form 1040 Line 4b. If blank, you determine it (usually the same as Box 1, unless there's after-tax basis). |
| Box 2b | "Taxable amount not determined" checkbox. Custodian can't determine your taxable amount because it depends on Form 8606 basis you may have. | If checked, you calculate the taxable amount yourself (or use Form 8606). |
| Box 4 | Federal income tax withheld from the distribution | Enters the withholding credits section of your 1040. Counts toward your total tax payments. |
| Box 7 | Distribution code — the most important box for inherited IRAs | Code 4 = death distribution. Tells the IRS no 10% early withdrawal penalty applies. See the full code table below. |
| Box 9b | Your total employee contributions (after-tax basis in the account) | Rarely filled in for IRAs (basis is tracked on Form 8606, not reported by the custodian). Relevant for inherited 401(k) or 403(b). |
Box 7 distribution codes for inherited accounts
The distribution code in Box 7 determines how the IRS treats the distribution. For inherited IRAs, you'll see one of these codes:1
| Code | What it means | When you'll see it |
|---|---|---|
| 4 | Death distribution — no 10% early withdrawal penalty, regardless of your age | Standard code for all inherited traditional IRA distributions to non-spouse beneficiaries |
| Q | Qualified Roth IRA distribution — entire distribution (including earnings) is tax-free | Inherited Roth IRA where the 5-year holding period has been met and the distribution is otherwise qualified |
| T | Roth IRA distribution, exception applies — principal is tax-free; earnings may or may not be taxable | Inherited Roth IRA where the 5-year period hasn't been satisfied, or the custodian can't confirm it; used with inherited Roth distributions |
| G | Direct rollover to an inherited IRA — not a taxable distribution | When you roll an inherited 401(k) or 403(b) directly to an inherited IRA via trustee-to-trustee transfer; not subject to withholding |
Where inherited IRA distributions go on Form 1040
For tax years 2020 and later, IRA distributions appear on two lines of Form 1040:2
- Line 4a — IRA distributions (total): Enter the gross amount from Box 1 of your Form 1099-R. This is every dollar distributed, including any portion that may be tax-free due to after-tax basis.
- Line 4b — IRA distributions (taxable amount): Enter the taxable portion. If the IRA had no after-tax basis, this equals Line 4a. If it did, this will be less (calculated using Form 8606).
If you received multiple 1099-Rs for the same inherited IRA (for example, from two separate custodians after a partial transfer), add the Box 1 amounts together for Line 4a and the Box 2a taxable amounts together for Line 4b.
After-tax basis: when the taxable amount is less than the gross distribution
If the decedent made non-deductible (after-tax) contributions to the IRA during their lifetime, a portion of every distribution is already-taxed basis — and you don't owe tax on it again. This basis transfers to you when you inherit the account.3
The calculation uses Form 8606 Part I for inherited IRAs. A few critical rules:
- Your inherited IRA has its own separate Form 8606. You cannot combine basis from an inherited IRA with basis from your own traditional IRA. Each is tracked and prorated independently.
- The custodian usually leaves Box 2a blank when basis exists (and checks the "taxable amount not determined" box). You are responsible for the calculation.
- If the decedent never filed Form 8606, the IRS may treat the entire IRA as pre-tax. In practice, you can reconstruct the basis from old tax returns or contribution records — but it requires documentation. A tax professional can help reconstruct this if you're certain non-deductible contributions were made.
If you're unsure whether the decedent made non-deductible contributions, check their final few years of tax returns for Form 8606, Part I. If you can't locate old returns, request transcripts from the IRS (Form 4506-T) going back up to 10 years.
Reporting an inherited Roth IRA distribution
Inherited Roth IRA distributions are reported on the same Form 1040 Lines 4a/4b, but the taxable amount is often zero. The distinction:
- Qualified distribution (Code Q): The Roth IRA had been open for at least 5 years from the original owner's first contribution year. Every distribution — contributions and earnings — is completely tax-free. Box 2a = $0. Line 4b = $0.
- Non-qualified distribution (Code T): The 5-year holding period hasn't been met. Contributions (original owner's basis) come out tax-free; earnings are taxable as ordinary income. You'll need Form 8606 to calculate the taxable earnings portion.
The 5-year clock transfers to you — you inherit the original owner's clock, not a fresh one. If your parent opened a Roth IRA in 2018 and died in 2025, the clock has run (5 years completed), and your distributions are qualified. See the inherited Roth IRA rules guide for the full breakdown including the defer-to-year-10 strategy.
Federal withholding on inherited IRA distributions
Withholding rules differ between IRAs and employer plans:4
- Inherited IRAs: Default withholding is 10%, but you can opt out entirely by completing Form W-4R (or checking the "no withholding" box on the distribution request form). There is no mandatory withholding on IRA distributions — you can always elect zero.
- Inherited 401(k) / 403(b) distributions: Mandatory 20% withholding applies to any direct cash distribution. This can be reduced only by doing a direct rollover to an inherited IRA, where no withholding occurs (Code G on the 1099-R).
Withholding is not tax — it's a prepayment of your eventual income tax liability. If too much is withheld, you get a refund. If too little is withheld (especially for large year-10 distributions or multiple inherited accounts), you may owe an underpayment penalty.
For large distributions, consider whether adjusting withholding on your other income sources or making estimated tax payments (Form 1040-ES) is more efficient than changing the inherited IRA withholding rate.
The § 691(c) IRD deduction: an often-missed Schedule A item
If the decedent's estate was large enough to owe federal estate tax, you are entitled to an income tax deduction each year you take distributions from the inherited IRA. This is the income in respect of a decedent (IRD) deduction under IRC § 691(c).
It works like this: a portion of the estate tax paid on the IRA asset is allocated to you as the income beneficiary. Each year, you deduct that pro-rata portion on Schedule A, Line 16 (other itemized deductions). The deduction pool can run to $50,000–$200,000+ on large inherited IRAs from taxable estates.
Under the OBBBA (July 2025), the federal estate/gift exemption is permanently set at $15 million per person ($30 million married).5 Fewer estates will owe estate tax now — but those that do (above the $15M threshold) will typically involve very large IRAs where the IRD deduction is substantial. The custodian never reports this deduction on the 1099-R; it requires you to obtain the estate's Form 706 and calculate the deduction pool yourself or with a tax professional.
Common reporting errors on inherited IRA tax returns
1. Accepting Code 1 on the 1099-R
As noted above: Code 1 means early distribution. Custodians occasionally file Code 1 for inherited IRA distributions, triggering an automatic 10% penalty on your return. Always verify Box 7 says Code 4. If it doesn't, request a corrected form before filing.
2. Combining inherited IRA basis with your own IRA basis on one Form 8606
Inherited IRA basis and your own traditional IRA basis are tracked on separate Forms 8606. If you merge them, you pro-rate across the wrong total balance and miscalculate the tax-free portion. Use one Form 8606 per inherited account, with its own balance and basis.
3. Not reporting a year-of-death RMD your custodian aggregated with yours
When an IRA owner dies partway through the year without completing their annual RMD, the remaining amount is your obligation. Some custodians issue one 1099-R for the year-of-death RMD amount. Make sure this amount appears on your return. See the year-of-death RMD guide for the calculation method and deadline (December 31 of the year of death).
4. Omitting required annual RMDs entirely — then needing to amend
If your inherited IRA is subject to annual RMD requirements (because the original owner had crossed their Required Beginning Date per T.D. 10001 rules), failing to take an RMD means you owe a 25% excise tax on the missed amount — reducible to 10% if corrected within two years via Form 5329. This creates an additional line on your tax return that many filers miss. See the missed inherited IRA RMD correction guide.
5. Entering the distribution on the wrong lines (5a/5b vs. 4a/4b)
IRA distributions go on Lines 4a/4b. Pension and annuity distributions (including employer plan distributions you haven't rolled to an IRA) go on Lines 5a/5b. Tax software generally handles this correctly if you input the 1099-R data accurately, but verify the placement when reviewing your draft return.
6. Missing the state tax return implications
Thirteen states fully exempt IRA distributions from state income tax, and five states impose a separate inheritance tax on the IRA balance itself. The federal Form 1040 mechanics don't capture either of these. Review the state taxes on inherited IRA guide for your state's rules before finalizing your state return.
When professional help is worth it
The 1040 mechanics are straightforward for a simple inherited IRA — one account, no after-tax basis, one beneficiary. You input the 1099-R into tax software and it flows correctly to Lines 4a/4b.
The situation escalates quickly in any of these scenarios:
- The IRA had after-tax basis and the decedent either never filed Form 8606 or filed it incorrectly
- You inherited from a large estate that paid federal estate tax and you need to calculate the § 691(c) deduction pool
- You received multiple 1099-Rs from a custodian transition, rollover, and annual distribution in the same year
- You're subject to annual RMDs under T.D. 10001 and need to separately track the RMD obligation vs. the voluntary excess distribution
- You took the year-of-death RMD, and the decedent's custodian issued the 1099-R in the decedent's name (not yours), creating a mismatch
- You live in or moved between states with different inheritance or income tax treatment
Get matched with a specialist
Fee-only advisor with no commission conflict. Free match.
Sources
- IRS Form 1099-R and 5498 Instructions — Box 7 distribution codes table, including Code 4 (death) definition.
- IRS Form 1040 Instructions — Lines 4a/4b (IRA distributions) and Lines 5a/5b (pensions and annuities) guidance.
- IRS Publication 590-B, Distributions from Individual Retirement Arrangements — Form 8606 instructions for inherited IRA after-tax basis; basis transfer rules under IRC § 408(d)(2).
- IRS Form W-4R, Withholding Certificate for Nonperiodic Payments and Eligible Rollover Distributions — optional withholding election for IRA distributions; mandatory 20% for eligible rollover distributions from employer plans.
- One Big Beautiful Bill Act (OBBBA), July 2025 — permanently sets federal estate and gift exemption at $15 million per person, affecting the universe of estates that owe estate tax and trigger the § 691(c) IRD deduction.
Filing mechanics verified against IRS Form 1099-R instructions, IRS Publication 590-B, and Form 1040 instructions as of June 2026. Tax law values (brackets, withholding rules) per IRS Rev. Proc. 2025-32 and current IRS guidance.