The CSED — the IRS collection statute expiration date — is the point at which the standard 10-year collection period generally ends. It is measured from the date of assessment, not from the return's filing date or its due date. Because the clock runs per assessment, an account with more than one assessment can carry more than one CSED. Treat any figure you see as a starting point for verification, not a settled conclusion: pending events can suspend or extend the period, so the date on your paperwork is only accurate as of the record that produced it.
What the official record establishes
The IRS page Time the IRS can collect tax states the general rule plainly: the IRS generally has 10 years from the date the tax was assessed to collect it plus associated penalties and interest. The same page notes that multiple assessments on a single account may each have their own CSED, and that an amended or additional assessment does not necessarily restart the original clock. It also lists circumstances that can suspend or extend collection time — a pending installment request, bankruptcy, an Offer in Compromise, a Collection Due Process hearing request, an innocent spouse claim, certain military service, and continuous foreign residence. Critically, that page notes a future-income levy issued before expiry may continue collecting afterward, so a CSED is not a guarantee that every payment obligation disappears at midnight. The page directs taxpayers to the CSED shown on the account transcript, and to contact the IRS using the details on the actual notice to verify the last day for a specific period or question the accuracy of a figure.
A practical review worksheet
Use a blank copy. One row per assessment, one column per fact you need to confirm.
| Field | Assessment 1 | Assessment 2 | Assessment 3 |
|---|---|---|---|
| Tax year / period | |||
| Assessment date shown on notice | |||
| CSED printed on transcript | |||
| Amount assessed | |||
| Original return filing date | |||
| Any additional or amended assessment? | |||
| Transcript type ordered | |||
| Pending event (installment request, OIC, CDP, bankruptcy, other) | |||
| Date asked IRS to verify last day | |||
| Contact route used (notice phone/number) | |||
| Verification outcome |
Review the evidence in order
- Separate the assessments. Before reading any date, list each assessment on the account. If you need the assessment and payment history rather than a summary, see Record of Account Transcript: When and How to Get It. For entry-level codes appearing in the account, IRS Code 290: Additional Tax and Zero-Dollar Entries explains what those lines represent.
- Pull the transcript. The IRS states the CSED can be found on the account transcript. Compare what the transcript shows against the notice in your file.
- Check whether a pending event exists. A signed, active installment plan and a pending request are different things. Note the start and end dates of any event you find, and get the IRS's own computation rather than building your own day-count.
- Ask the IRS to confirm. Use the contact information on the notice. If you disagree after receiving an IRS explanation, the page describes Taxpayer Advocate Service help.
- Write down what you verified, when, and from which source. This is the record that survives later staff changes.
Related: a CSED question often sits beside an offer question. Form 656: Review Your Offer in Compromise Application covers which booklet applies, and Offer in Compromise Calculator: Use an Estimate Wisely covers what the pre-qualifier does and does not tell you. An application can affect collection timing — an estimate run through a calculator is not an application.
Hypothetical example
Hypothetical example: a file contains an original assessment, a later additional assessment and records of a pending offer. The reviewer records each assessment separately, gathers the event dates and asks the IRS to confirm the applicable CSEDs. The example does not compute a deadline or presume the later assessment restarted the original period.
- [ ] Listed every assessment separately
- [ ] Confirmed the CSED shown on the transcript
- [ ] Noted any pending event affecting the period
- [ ] Asked the IRS to verify the last day for the specific period
- [ ] Recorded the source, date, and route of verification
- [ ] Saved the worksheet with the file
FAQ
Does the 10 years run from the filing date or the due date?
No. The IRS describes it as running from the assessment date.
Does a second assessment on the same account restart everything?
Not necessarily. Each assessment is separate, and an additional assessment does not automatically restart the original clock. Verify each one on the transcript.
If my CSED has passed, is collection over?
Not automatically. The IRS page notes that a future-income levy issued before expiry may continue afterward, and that the CSED differs from assessment and refund limitation dates. Confirm the specific facts with the IRS.
For tax firms
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