By Rick Yandle, Esq., CPA — federal criminal & civil tax defense
Here is the short version most taxpayers never hear: the IRS does not have unlimited time. It generally gets three years to assess additional tax and ten years to collect it — and knowing exactly where those two clocks stand can quietly change your options in a dispute.
Most of the attention in a tax dispute goes to the substance — what was owed, what was deducted, who was right. But some of the most consequential moves have nothing to do with the merits and everything to do with time. Understanding the statutes of limitations turns the calendar from a source of dread into something that can actually work in a taxpayer's favor.
Two clocks, not one
There are really two separate deadlines, and confusing them causes a lot of needless worry.
The first is the assessment statute. As a general rule, the IRS has three years from the date a return is filed to assess additional tax; a return filed before its due date generally counts as filed on the due date (26 U.S.C. Section 6501(a), (b)(1)). For income tax, that window generally stretches to six years when the return omits includible gross income exceeding 25% of the gross income stated on the return (Section 6501(e)(1)(A)). And there is no ordinary assessment deadline at all for a fraudulent return or when no return was filed — along with some additional specialized exceptions under Section 6501(c). No return, no clock — a hard truth for non-filers who assume time is quietly helping them. It is not.
The second is the collection statute. Once tax is properly assessed, the IRS generally has ten years to collect it (Section 6502) — the "collection statute expiration date," or CSED. After that date, absent something that paused or extended the clock, the debt is no longer collectible.
Knowing which clock you are on, and how much time is left on it, is the starting point for almost every collection-defense decision.
The consent trap: think hard before you waive
Here is the moment where taxpayers most often give away an advantage without realizing it. During an audit, when the assessment clock is running low, the IRS will frequently ask the taxpayer to sign a consent extending it — Form 872 (to a fixed date) or Form 872-A (open-ended, until affirmatively terminated). The request is routine and the form looks harmless. Signing is often presented as the cooperative, sensible thing to do.
Sometimes it is. But it is not automatic, and it should never be reflexive. Declining to extend can force the IRS's hand: if the agency wants to preserve its ability to assess, it may have to finish its work and issue a notice of deficiency now, on the record it has, rather than keep the examination open indefinitely. Whether to extend, for how long, and on what terms is a genuine strategic decision — one that depends on the strength of the IRS's position, the state of your documentation, and how close the clock is to running out. The point is simply this: a consent gives the IRS more time to build its case against you. That is not something to hand over without a reason.
Riding out the clock
In periods when the IRS is stretched thin, cases move more slowly, and the collection statute becomes a more realistic factor in planning than it is in flush years. For some taxpayers with older liabilities, letting the CSED do its work — while staying compliant and avoiding anything that would suspend the clock — has become a viable part of the strategy rather than a long-shot hope. Whether that fits a given case depends entirely on the specific dates and facts, and on avoiding the many actions (certain requests, agreements, and filings) that can pause or extend the collection period.
The practical takeaway
The statute of limitations is not a technicality to mention in passing. It is a structural feature of every tax controversy, and it rewards taxpayers who track the dates and make deliberate decisions — especially the decision of whether to give the IRS more time. Before signing any consent to extend, and before assuming that time is or isn't on your side, it is worth mapping exactly where both clocks stand.
A note for referring counsel
If you have a client under examination or in collection, the assessment and collection statutes can quietly control the outcome — and a consent signed without analysis can forfeit real leverage. I am glad to consult with counsel and CPAs on the timing dimension of a tax matter before a deadline decision is made.
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