IRS Collection Statute of Limitations and Tolling: CSED and Form 900

The IRS statute of limitations on collections is ten years, measured from the date the tax was formally assessed. That deadline is tracked internally as the Collection Statute Expiration Date, or CSED. Once it passes, the IRS loses its legal authority to collect the balance through levies, wage garnishments, or lawsuits.¹ The complication is that a long list of ordinary taxpayer actions pauses that clock, sometimes adding years to the original window.

The Ten-Year Rule

Federal law lets the IRS collect an assessed tax by levy or by court proceeding, but only if it acts within ten years after the assessment date.¹ The assessment date is the moment the IRS officially records the liability on its books. For most people that happens when a filed return is processed showing a balance due. If the IRS later audits and determines additional tax, that additional amount gets its own separate assessment date. Each tax year and each assessment carries its own CSED, so one taxpayer can have several deadlines running at once.

When the ten-year window closes without full payment, the remaining balance becomes legally unenforceable. No more levies, no more garnishments, no more lawsuits. Any federal tax lien tied to the expired liability must be released within 30 days once the IRS confirms the debt is unenforceable.² If you made payments after your CSED passed, you can request a refund of those overpayments.³

How To Find Your Assessment Date and CSED

The clock does not start until the IRS makes a formal assessment. On your account transcript, Transaction Code 150 marks the date a return was filed and the initial tax recorded. Transaction Code 300 indicates an additional assessment from an audit.⁴ Those dates anchor your ten-year windows.

You can pull the transcript by signing in to your IRS Online Account, calling the automated transcript line at 800-908-9946, or mailing Form 4506-T. In the Transactions section, look for the three-digit code and the date beneath it. The IRS notes that the CSED it shows generally reflects tolling time already added by law.³

If You Never Filed, the Clock Never Starts

No return means no assessment, and no assessment means no CSED. The IRS can eventually file a Substitute for Return on your behalf, assess the tax, and start the collection period from that later date. Not filing does not run out the clock. It only postpones the start while interest and penalties accumulate.³

What Pauses the Ten-Year Clock

Tolling is where taxpayers most often lose track of their own deadline. Every event below suspends the CSED, and the effect stacks. Someone who files an Offer in Compromise that takes 18 months to resolve, then enters a three-year installment agreement that gets terminated, and then requests a Collection Due Process hearing can easily add three or more years to the original ten.

Offers in Compromise

Submitting an Offer in Compromise suspends the collection statute while the IRS reviews the proposal. If the offer is rejected, the clock stays paused for another 30 days. If you appeal within that window, the suspension continues through the entire appeals process.⁵ A contested OIC that drags on for a year adds that entire year to your CSED. You are buying time to negotiate, but you are also giving the IRS more time to collect if the offer fails.

Collection Due Process Hearings

When the IRS sends a notice of intent to levy or files a federal tax lien, you have the right to request a Collection Due Process hearing. Filing that request suspends both levy activity and the running of the collection statute for as long as the hearing and any court appeals stay pending.⁶ After the final determination, the statute cannot expire for at least another 90 days.

Installment Agreements

The statute is suspended while an installment agreement request is pending. If the request is rejected, the pause continues for 30 days, plus the duration of any appeal. While an approved agreement is active, the clock keeps running, but the IRS cannot levy your property. If the IRS terminates the agreement, the clock pauses again for 30 days plus any appeal.⁵

Separately, the IRS may ask a taxpayer entering certain installment agreements to sign a written waiver that extends the collection period beyond the original ten years. The statute permits this when the extension is agreed to in writing at the time the installment agreement is entered into.¹ More on that below.

Innocent Spouse Claims

If you filed a joint return and claim Innocent Spouse relief, the collection clock against you pauses from the date you file through the IRS investigation and any Tax Court petition. After the final determination, it stays paused for another 60 days.⁷

Bankruptcy

A bankruptcy filing triggers an automatic stay that stops most collection.⁸ The CSED is suspended for the entire period the case is open, plus an additional six months after discharge or dismissal.⁹ A Chapter 13 case that lasts three to five years adds that entire period plus six months. Even a Chapter 7 that wraps up in a few months adds those months plus another half year. Bankruptcy may discharge certain older tax debts, but any that survive come back with a longer collection runway.

Time Spent Outside the United States

If you are continuously outside the country for six months or more, the collection statute is suspended for the entire time you are abroad. When you return, the clock cannot expire until at least six months after you are back on U.S. soil.¹⁰ Short trips under six months do not trigger the suspension.

Combat Zone Service

Service members deployed to a designated combat zone or contingency operation get broader relief. The CSED is suspended for the duration of service, any continuous hospitalization from injuries sustained in the zone, and 180 days after service or hospitalization ends. The same protection extends to a deployed service member’s spouse.¹¹

A DOJ Lawsuit Resets the Timeline

The IRS can refer a case to the Department of Justice for a suit to reduce the tax debt to a court judgment. If the suit is filed before the CSED expires, the statute is suspended for the entire litigation.¹ Once judgment is entered, the IRS internally records a new CSED of 20 years from the judgment date.¹² The IRS reserves this step for larger liabilities where collection time is running short and the taxpayer has income or assets worth pursuing.

Form 900 Waivers Extend the Deadline Voluntarily

In some negotiations, usually for a Partial Payment Installment Agreement whose schedule would outlast the remaining CSED, the IRS asks the taxpayer to sign Form 900, the Tax Collection Waiver. Signing gives the IRS additional years to collect through the payment plan rather than forcing immediate collection action.

The waiver has limits. Form 900 must be signed before the original CSED expires. Extensions are capped at five years beyond the original CSED, plus up to one additional year to account for changes in the agreement.¹³ No one is required to sign, and refusing is not illegal. But the IRS may decline a long-term payment plan without a signed waiver, which is the real leverage behind the request.

Tracking Your CSED and Enforcing the Deadline

The IRS tracks tolling adjustments internally, but the practical burden of knowing where you stand falls on you. Pull an account transcript periodically and read the transaction codes for events that suspend the clock. If the IRS tries to collect on a balance you believe has expired, you can request a Collection Due Process hearing to challenge the action or submit a written request for lien release. If you made payments after your CSED passed, the IRS may notify you and offer a refund of those overpayments.³

1
Office of the Law Revision Counsel. 26 USC 6502 – Collection After Assessment
2
Office of the Law Revision Counsel. 26 USC 6325 – Release of Lien or Discharge of Property
3
Internal Revenue Service. Time IRS Can Collect Tax
4
Taxpayer Advocate Service. Decoding IRS Transcripts and the New Transcript Format: Part II
5
Office of the Law Revision Counsel. 26 USC 6331 – Levy and Distraint
6
Office of the Law Revision Counsel. 26 US Code 6330 – Notice and Opportunity for Hearing Before Levy
7
Office of the Law Revision Counsel. 26 USC 6015 – Relief From Joint and Several Liability on Joint Return
8
Office of the Law Revision Counsel. 11 USC 362 – Automatic Stay
9
Office of the Law Revision Counsel. 26 USC 6503 – Suspension of Running of Period of Limitation
10
Office of the Law Revision Counsel. 26 USC 6503 – Suspension of Running of Period of Limitation – Section: Taxpayer Outside United States
11
Office of the Law Revision Counsel. 26 US Code 7508 – Time for Performing Certain Acts Postponed by Reason of Service in Combat Zone or Contingency Operation
12
Internal Revenue Service. Collection Statute Expiration
13
Internal Revenue Service. Internal Revenue Manual – Partial Payment Installment Agreements and the Collection Statute Expiration Date (CSED)