Back taxes: what they are and what to do about them

What back taxes mean and how they build up

The term back taxes simply means tax from a past year that has not been paid in full. The IRS does not use a special label for it: your account shows a balance for each tax year, and each balance keeps growing until it reaches zero.

Most back taxes owed to the IRS start in one of four ways. You filed but could not pay the balance due. You never filed, and the IRS later built a return for you from W-2 and 1099 data. The IRS changed your return after matching income records, as with a CP2000 notice. Or an audit ended with additional tax assessed. Our page on why you might owe back taxes walks through each cause.

Three charges stack on the original tax

• Failure-to-pay penalty: 0.5% of the unpaid tax for each month or part of a month, capped at 25%.
• Failure-to-file penalty: 5% of the unpaid tax per month or part of a month, capped at 25%, if the return itself was late. For a return more than 60 days late, the minimum is $525 or 100% of the tax, whichever is less, for returns due after December 31, 2025.
• Interest: the federal short-term rate plus 3 points, set every quarter and compounded daily. It is 7% for July through December 2026. The January to March 2027 rate is not yet announced; the IRS usually publishes it in late November.

Interest also runs on the penalties themselves. If a penalty is later removed, the interest charged on that penalty comes off automatically.

Step one: confirm the back taxes IRS records show

Before you pay anyone or sign up for anything, look at the balance on the IRS side. The quickest route is your IRS Individual Online Account, which lists what you owe by tax year, up to five years of payment history and digital copies of certain notices. Our guide on how to check if you owe back taxes covers sign-in, transcripts and why the total moves each day.

Check three things on every notice or balance screen: the tax year, the form (usually 1040 for individuals) and the notice number printed in the upper or lower right corner. Those three details decide which payment option applies and where a payment must be credited.

Your options when you owe back taxes and cannot pay

Paying in full stops the monthly penalty and the daily interest right away. If that is not possible, the IRS has several standard arrangements. None of them erases interest, and most keep some penalty running until the balance is gone.

A plan also cuts the late payment penalty. If you filed on time and have an approved plan, the rate falls from 0.5% to 0.25% per month. Low-income applicants, defined as adjusted gross income at or below 250% of the federal poverty guidelines, have the direct-debit setup fee waived.

For a side-by-side look at which choice costs the least, read can't pay taxes: your IRS options. If you already know the amount and want to send money, go to how to pay back taxes.

What the IRS can do about unpaid back taxes

Collection follows a set order, which gives you time to act. A first bill (CP14) is followed by reminders (CP501, CP503), a Notice of Intent to Levy (CP504) and then a Final Notice of Intent to Levy and Notice of Your Right to a Hearing (LT11 or Letter 1058).

After the final notice, the IRS must wait at least 30 days before levying. You can request a Collection Due Process hearing on Form 12153 within that 30-day window. Levies can reach wages, bank accounts, Social Security benefits and other property, and a bank levy holds your funds for 21 days before the bank sends them.

Other consequences run alongside the letters. A federal tax lien can attach to everything you own now and later. Future federal and state refunds can be taken. If your total, including penalties and interest, passes the seriously delinquent threshold ($66,000 for 2026; the 2027 figure is not yet announced and usually appears in October or November), the IRS can certify the debt to the State Department and your passport can be denied or revoked.

The full month-by-month picture is on what happens if you don't pay taxes.

A worked example of back taxes growing

Say you filed your 2025 return on time but left $6,000 unpaid on April 15, 2026. Here is roughly how the balance moves over one year if nothing is paid and the higher 1% rate that follows an ignored levy notice never applies.

The figures are rounded and assume the 7% rate holds all year. Had the return also been filed late, the failure-to-file penalty would have added up to 22.5% more in the first five months, which is why filing on time matters even when you cannot pay.

First five steps if you owe back taxes

1. Open your IRS online account and write down the balance for each tax year.
2. File any missing returns, even if you cannot pay what they show.
3. Pay whatever you can now through Direct Pay or your online account to shrink the base that penalties and interest grow on.
4. Pick an arrangement for the rest: short-term plan, installment agreement, Offer in Compromise or hardship status.
5. Answer every notice by its deadline, especially an LT11 or Letter 1058, where the 30-day hearing window matters.

If the deadline on a notice is close and you are still gathering paperwork, contact the IRS using the number on the notice. Asking for time on a specific notice is usually better than letting it pass.

Where each back taxes problem is covered

Use this map to go straight to the page that fits your situation.

• You just got a bill and want the basics: owe IRS money? what happens next.
• You owe for the 2026 tax year and the April 15, 2027 deadline is coming: owing taxes in 2027.
• You want to pay from your bank account for free: IRS Direct Pay guide.
• You are weighing bankruptcy: the tax debt and bankruptcy page in this cluster explains which income tax debts can be discharged.
• You have questions about paying by check in the future: the page on the IRS electronic payment requirement tracks the Executive Order 14247 changes.

Checks and money orders are still accepted for payments to the IRS as of September 2026. The IRS expects any electronic-only payment rule not to start before 2027, and no exact date has been published.