The Complete IRS Collections Timeline: Every Deadline From First Notice to CSED
A Federal Tax Desk reference — verified against live IRM 5.1.19 and reviewed by Forrest Baumhover, July 20, 2026
Part 1 — The Notice Sequence (Before Levy Authority)
CP14 — First balance-due notice, sent after a return posts with tax owed. Deadline: pay or respond within 21 days. Authority: IRS.gov, Understanding Your CP14 Notice; Taxpayer Advocate Service.
CP501 — First reminder if CP14 goes unanswered. Authority: IRS Best Practices for Responding to IRS Collection Notices.
CP503 — Second reminder, firmer tone. Authority: same source.
CP504 — Final notice before levy on state refund and other property. Authority: IRC §6331(d); IRS.gov, Understanding Your CP504 Notice.
LT11 / Letter 1058 — Final Notice of Intent to Levy and Notice of Your Right to a Hearing. Deadline: 30 days to request a Collection Due Process hearing. Authority: IRC §6330.
Letter 3172 — Notice of Federal Tax Lien Filing and Your Right to a Hearing. Authority: IRC §6320.
The IRS does not publish a fixed interval between CP501, CP503, and CP504 — each notice fires based on the account’s status in IRS processing (IRM 5.19.1), not a set calendar. In practice, practitioners typically see 4–8 weeks between each notice, but the only reliable date for a given case is the one printed on that notice. Don’t advise a client on a fixed countdown between reminder notices; watch the mail.
Part 2 — The Collection Statute Expiration Date (The Outer Boundary)
Base rule: 10 years from assessment date. IRC §6502(a)(1).
That clock pauses (tolls) during these events:
Bankruptcy — 11 U.S.C. §362; IRC §6503(h); IRM 5.1.19.3.1.
Collection Due Process (CDP) hearing (a right to a hearing before levy) — IRC §6330(e)(1); IRM 5.1.19.3.3.
Offer in Compromise (OIC), pending — IRC §6331(k)(1) and (3); IRM 5.1.19.3.4.
Installment agreement — IRC §6331(k)(2) and (3); IRM 5.1.19.3.5. (Written-waiver PPIAs under Form 900 run under §6502(a)(2) instead — a separate, narrower case covered here only in passing.)
Innocent spouse request — IRC §6015(e); IRM 5.1.19.3.6.
Taxpayer living outside the U.S. (6+ months) — IRC §6503(c); IRM 5.1.19.3.7.
Combat zone or contingency operation service — IRC §7508; IRM 5.1.19.3.8.
Military service (Servicemembers Civil Relief Act / SCRA) — 50 U.S.C. §4000, service plus 270 days after; IRM 5.1.19.3.9.
Combat zone service and SCRA military deferment are separate, independently-tolling categories — a service member can qualify for one, both, or neither, depending on duty status and financial hardship. Don’t assume a “military” client only triggers one.
A standalone Tax Court petition or a bare audit/examination does not independently toll the CSED under current IRM — there’s no freestanding “Tax Court” or “audit” category here, unlike bankruptcy or CDP. Tax Court proceedings do extend suspension length inside the innocent-spouse and CDP categories above (for example, an innocent-spouse suspension runs until a Tax Court decision is final, plus 60 days) — but only as part of those existing categories, not as a category of their own.
Worked example: Assessment 4/15/2020 → base CSED 4/15/2030. OIC submitted 6/1/2024, rejected 9/1/2024, not appealed. Suspension runs 6/1 through 10/1/2024 (rejection date plus the 30-day appeal window) = 122 days. New CSED: 8/15/2030.
Overlapping events don’t stack. When two or more tolling events overlap, the suspension counts the overlapping days once — not once per event (IRM 5.1.19.3(2)). A client with a pending OIC during a period of military deferment doesn’t get both suspensions added together for the days they overlap; only the combined span, from the earliest event’s start to the latest event’s end, counts.
Part 3 — The Close
Every deadline above is a countdown, and the one that matters most — the CSED — is the hardest to track by hand, especially once tolling events start stacking. The Federal Tax Desk built a free CSED Calculator that runs this exact math and cites the exact IRM subsection behind every tolling day, the same authorities above. Run it once a case has any tolling history and see the date, not just the arithmetic.
This resource is designed for use by licensed tax professionals. It is not legal or tax advice and should not be relied upon without professional review.