If you forgot to file a 1099-R, file an amended return on Form 1040-X as soon as you can, or respond directly to the IRS notice if one has already arrived. The financial institution that paid the distribution sent the same 1099-R to the IRS, so the gap between what you reported and what the IRS has on file will surface. Moving quickly limits the interest and penalties that pile up on unpaid tax and puts you in a much better position to ask for penalty relief.
The IRS Already Has a Copy
Any retirement plan, IRA custodian, annuity provider, or pension fund that pays out $10 or more files a copy of Form 1099-R with the IRS. That data runs through the Automated Underreporter system, which matches every information return the IRS receives against what appears on your Form 1040.1Internal Revenue Service. IMF Automated Underreporter Program When the numbers disagree, a notice follows.
Matching isn’t quick. A missing 1099-R often takes a year or more to surface, which can create a false sense of safety. The interest clock, though, starts the day after your original tax due date, regardless of when the IRS gets around to noticing.
What It Costs to Wait
Three charges stack up on unreported distribution income: a failure-to-pay penalty, a possible accuracy-related penalty, and interest.
Failure-to-Pay Penalty
The failure-to-pay penalty is 0.5% of the unpaid tax for each month or partial month the balance sits, capped at 25%. Set up an IRS-approved payment plan and the rate drops to 0.25% per month while the plan is active.2Internal Revenue Service. Failure to Pay Penalty Ignore the IRS long enough to receive a levy notice and it jumps to 1% per month.
Accuracy-Related Penalty
If the omitted income creates a “substantial understatement” on your return, the IRS can add 20% of the underpaid tax on top.3Internal Revenue Service. Accuracy-Related Penalty Substantial means an understatement greater than the larger of 10% of the tax that should have been shown on the return or $5,000.4Office of the Law Revision Counsel. 26 US Code 6662 – Imposition of Accuracy-Related Penalty on Underpayments A sizeable retirement distribution clears that bar without much trouble.
Interest
Interest accrues from the original due date of the return and compounds daily.5eCFR. 26 CFR 301.6622-1 – Interest Compounded Daily The rate adjusts quarterly and equals the federal short-term rate plus three percentage points; for the quarter beginning April 1, 2026, the individual underpayment rate is 6%.6Internal Revenue Service. Internal Revenue Bulletin 2026-08 Unlike penalties, interest can’t be waived, so every day you delay adds to the bill.
If a CP2000 Notice Has Already Arrived
When the IRS catches the miss before you do, the notice you’ll see is a CP2000. It isn’t a bill. It’s a proposal that lays out the missing income, the additional tax the IRS thinks you owe, the penalties, and the interest.7Internal Revenue Service. Topic No 652, Notice of Underreported Income – CP2000
You have 30 days from the notice date to respond, or 60 days if you live outside the United States.7Internal Revenue Service. Topic No 652, Notice of Underreported Income – CP2000 You can respond through the IRS Document Upload Tool, by fax, or by mail. If the proposed changes are right, sign the agreement portion and pay. If they aren’t, check the disagree box, attach a signed statement, and include documentation.
Do not ignore the notice. Silence produces a Statutory Notice of Deficiency, which formally assesses the tax.7Internal Revenue Service. Topic No 652, Notice of Underreported Income – CP2000
One procedural point worth flagging: if you’ve already received a CP2000, respond to it rather than filing a separate 1040-X. The Automated Underreporter unit handles the notice, and a standalone amended return goes to a different processing group, which slows everything down.
Filing Form 1040-X Before the IRS Contacts You
If nothing has arrived yet, Form 1040-X is the right move. Voluntary correction shows good faith and strengthens any later request for penalty relief.
The general deadline is three years from the date you filed the original return, or two years from the date you paid the tax, whichever is later.8Internal Revenue Service. File an Amended Return Watch one wrinkle: if the omitted distribution pushes unreported income above 25% of the gross income shown on the original return, the IRS has six years to assess additional tax rather than the usual three.
On the form itself, Column A holds the figures from your original return, Column C holds the corrected figures with the 1099-R added, and Column B shows the difference. Part III asks for an explanation; a plain statement like “Adding previously omitted retirement distribution reported on Form 1099-R” is enough. Attach a copy of the 1099-R and any schedules the additional income touches.
Form 1040-X can be e-filed through tax software for the current year and the two prior tax periods, or mailed on paper.9Internal Revenue Service. About Form 1040-X, Amended US Individual Income Tax Return Processing generally runs 8 to 12 weeks, and sometimes up to 16.10Internal Revenue Service. Amended Return Frequently Asked Questions
If the amendment produces additional tax, send payment with the 1040-X or pay electronically. Every dollar paid stops interest from accruing on that amount going forward.
If the Distribution Was Actually a Rollover
This is where a lot of unnecessary panic lives. Money moved from one retirement account to another isn’t taxable, as long as it landed in the new account within 60 days.11Office of the Law Revision Counsel. 26 USC 402 – Taxability of Beneficiary of Employees Trust But the payer still issues a 1099-R for the money that left the account, and if the rollover wasn’t reported on your return, the IRS treats the full amount as taxable.
To fix it, file Form 1040-X, report the distribution, and mark the taxable portion as zero (or only the portion you didn’t roll over). Keep a statement from the receiving institution showing the deposit date and amount.12Internal Revenue Service. Topic No 413, Rollovers From Retirement Plans
Missed the 60-day deadline? The IRS can waive it in cases involving casualty, disaster, or other circumstances beyond your reasonable control, and there is a self-certification procedure for automatic waivers.11Office of the Law Revision Counsel. 26 USC 402 – Taxability of Beneficiary of Employees Trust Forgetting or spending the money isn’t grounds for a waiver; in that case the distribution is taxable.
Early Withdrawal: Check Form 5329 Before Paying the 10%
If the distribution came out before age 59½ and Box 7 of the 1099-R shows code “1,” the IRS expects a 10% additional tax on the taxable portion.13Internal Revenue Service. Retirement Topics – Exceptions to Tax on Early Distributions Include Form 5329 with your amended return to calculate it.
Several exceptions eliminate that 10%, even when the distribution is technically early. Common ones:
- Separation from an employer’s service in or after the year you turned 55, for distributions from that employer’s plan (not an IRA).
- Substantially equal periodic payments over your life expectancy, sometimes called 72(t) distributions.
- Total and permanent disability supported by medical documentation.
- Unreimbursed medical expenses above 7.5% of your adjusted gross income.
- Qualified higher education expenses, for IRA distributions.
- First-home purchase, up to $10,000 from an IRA.
If an exception applies but Box 7 doesn’t reflect it, file Form 5329 with the correct exception code.14Internal Revenue Service. Instructions for Form 5329 Plenty of people pay the 10% penalty when they didn’t have to, so this is worth checking carefully.
Getting the Penalties Reduced
First Time Abate
If this is your first slip, First Time Abate can wipe out the failure-to-pay penalty entirely. You qualify if you filed the required returns for the three tax years before the penalty year and had no penalties (or had all penalties removed for an acceptable reason) during that same period.15Internal Revenue Service. Administrative Penalty Relief Ask by phone or in writing once you’ve filed the corrected return and paid the tax. First Time Abate covers failure-to-file and failure-to-pay. It does not cover the accuracy-related penalty or interest.
Reasonable Cause
If you don’t qualify for First Time Abate, you can request relief by showing reasonable cause. The IRS looks at whether you exercised ordinary care despite the failure. Serious illness, a death in the family, natural disasters, and inability to obtain necessary records tend to support the argument. Claiming you didn’t know you had to report the income, blaming a tax preparer, or saying you simply overlooked the form generally does not.16Internal Revenue Service. Penalty Relief for Reasonable Cause
For either type of relief, document what you did once you discovered the problem. Filing the amended return and paying the tax before the IRS contacts you is the single strongest fact you can put in front of an examiner.