How long does the IRS have to collect a tax debt?

Ten years from the date of assessment under IRC 6502(a)(1), plus any periods during which the clock is suspended, unless the IRS files a timely collection suit or a valid written extension applies.

Does the ten years start from the tax year or the due date?

Neither. It runs from the date each tax is assessed. Different assessments for the same year can have different expiration dates.

What happens to a federal tax lien when the CSED expires?

Under IRC 6322, the lien continues until the liability is satisfied or becomes unenforceable by reason of lapse of time. When collection becomes time-barred, the lien no longer has a liability to secure.

Can the IRS keep money it collects after the CSED?

IRC 6401(a) treats amounts collected after the limitation period as overpayments. IRM 5.1.19.4 does allow proceeds from a levy served, or assets seized, before the CSED to be applied after it.

The Ten-Year Collection Statute: The Legal Rules Behind the CSED

Once the IRS assesses a tax, a second clock starts. The IRS has ten years to collect it by levy or by a lawsuit. When that period expires, the IRS's power to collect the assessment ends. Inside the IRS the expiration date is called the CSED, for Collection Statute Expiration Date.

This guide covers the legal rules: what starts the clock, what the IRS has to do before it runs out and what the expiration actually accomplishes. It does not walk through day counting. The point here is to understand what the date means so you can plan around it.

The statute

Section 6502(a) of the Internal Revenue Code says that where the assessment of any tax has been made within the applicable period of limitation, the tax may be collected by levy or by a proceeding in court, but only if the levy is made or the proceeding begun within 10 years after the assessment of the tax.

There is a second branch for written extensions. Section 6502(a)(2) allows collection after ten years in two narrow situations: when there is an installment agreement and the IRS and the taxpayer agreed in writing, at the time the agreement was entered into, to a longer period, in which case collection can continue until 90 days after the agreed period expires; and when there is a release of levy under section 6343 after the ten-year period, in which case collection can continue until the period agreed in writing before the release expires. Those waivers are covered in the guide to Form 900.

Ten years was not always the number. A statutory amendment note to section 6502 shows that Congress substituted 10 years for 6 years in 1990, applicable to taxes assessed after November 5, 1990 and to earlier assessments whose collection period had not expired by then.

The clock runs from assessment, not from the tax year

The CSED is measured from the date of assessment. It is not measured from the end of the tax year, the due date of the return or the date you received a bill. For a return filed late, assessment happens after the return is processed. For an audit, the additional tax is assessed after the deficiency process ends, often years after the tax year.

Each assessment has its own clock. A single tax year can have several assessments: the tax shown on the original return, an audit deficiency, a later penalty. IRM 5.1.19.4 notes that penalties may have a different CSED from other assessments on the same module, and IRM 5.1.19.3.15 explains that an additional assessment after a substitute for return gets its own CSED. Your account transcript shows the assessment dates.

What the IRS must do before the CSED

The statute is satisfied if a levy is made or a court proceeding is begun within the ten years. Section 6502(b) says the date a levy on property is made is the date the notice of seizure under section 6335(a) is given.

If the IRS files a timely collection lawsuit, the last sentence of section 6502(a) extends the period for collection by levy until the liability, or a judgment arising from it, is satisfied or becomes unenforceable. The guide to suits to reduce tax to judgment explains that path.

IRM 5.1.19.4 adds two collection-side details. Proceeds from the sale of assets seized before the statute expired can be applied after the expiration date, and proceeds from a levy served before the CSED may be applied to the expired modules.

What expiration accomplishes

When the CSED passes with no timely levy, lawsuit or extension, the IRS can no longer collect the assessment by levy or court action. Several other consequences follow from other Code sections.

The federal tax lien ends. Section 6322 says the lien arises at assessment and continues until the liability is satisfied or becomes unenforceable by reason of lapse of time.
Payments collected after expiration are overpayments. Section 6401(a) defines overpayment to include any part of a tax payment assessed or collected after the applicable limitation period expired. See the guide on payments after the CSED.
The IRS cannot offset refunds against the expired debt. Section 6514(b) says a credit against a liability is void if any payment on that liability would be an overpayment under section 6401(a).
The IRS should not ask you to pay. IRM 5.1.19.4 tells employees not to solicit voluntary payments on accounts barred by statute.

What can move the date

The ten years are not always ten calendar years. A number of events suspend the running of the collection period, meaning the clock stops and later resumes. Section 6503 covers several, including bankruptcy, time spent outside the United States and assets in court custody. Section 6331(k) suspends the period while certain offers in compromise and installment agreement requests are pending. A timely collection due process hearing request suspends it under section 6330(e).

Those events are covered one by one in the guide on what suspends the collection statute. The legal rule to remember here is that the CSED is ten years from assessment plus any suspension periods, plus any period agreed in a valid written extension.

What the CSED does not do

It does not stop the IRS from collecting before the date. Ten years is the outside limit, not a grace period. Levies, liens and offsets all remain available until the date arrives.

It does not apply to assessment. The collection period starts only once tax is assessed. A year with no assessment has an assessment statute problem first.

It does not run from the oldest year for everything. Each assessment carries its own date, so some balances expire while others remain.

And it does not mean the IRS will be passive as the date approaches. IRM 5.1.19.5 defines an imminent CSED as one with 12 months or less remaining and directs revenue officers to work imminent CSEDs timely as priority cases. Expect attention, not silence, in the final year. The strategy for that period is covered in the guide to planning near the CSED.

Reading your own dates

Your IRS account transcript lists each assessment and its date, and it shows transaction codes for events that may suspend the clock. The IRS's own IRM 5.1.19 warns its employees that the CSED shown on its systems may not be correct because of simultaneous actions suspending or extending it, and that suspensions under IRC 7811(d) for Taxpayer Advocate requests are not entered on its systems at all.

In other words, the date on the screen is a starting point. The legal date is ten years from assessment, adjusted by the events that actually happened. Getting that right is worth the effort, because every collection decision depends on it.

Common misreadings of the ten-year rule

The ten years started when I filed. Filing starts the assessment clock. The collection clock starts at assessment, which may be the same day or years later.
The oldest year expires first, so everything expires then. Each assessment has its own date.
If the IRS stops calling, the clock stops too. Silence is not a suspension event. Only the statutory events do that.

The bottom line

The IRS has ten years from each assessment to collect by levy or lawsuit under IRC 6502(a), extended only by suspension events, a timely lawsuit or a narrow written waiver. When the date passes, collection authority ends, the lien ends and later payments become overpayments.

If you owe old balances, find the CSED for each one before you choose a resolution. The calendar often decides which option makes sense.