What a CP259 is
A CP259 is the IRS telling a business that a return it was expecting has not arrived. The notice: "Our records show that you haven't filed your tax return for the tax period ending on [date]."
It is generated because the business has a filing requirement on record for that form. That requirement was created when the EIN was issued and it does not switch itself off when the activity stops — which is the single most common reason these letters arrive at businesses that owe nothing at all. The IRS explains it plainly:
"When you apply for an EIN, filing requirements are established for specific types of returns to be filed (e.g. Form 940, Employer's Annual Federal Unemployment Tax Return; Form 941, Employer's Quarterly Federal Tax Return; Form 1120, U.S. Corporation Income Tax Return, etc.). When the return is not filed, the IRS considers it to be delinquent and sends a notice requesting the return be filed."
A CP259 is the business twin of the CP59, the individual non-filer notice. Same instrument, different account. CP59, the individual version →
And this is worth saying out loud, because it is the thing people are braced for. A CP259 is not an accusation and it does not mean anyone thinks you were hiding. It means a box on a computer record says a form is expected and none has posted against it. Businesses that closed cleanly, businesses that never had employees, and businesses that moved to annual filing all generate these.
Sources: IRS Notice CP259 sample notice, and IRS, "Understanding your CP259 notice," both read 6 September 2026.
Your clock, and the one date on the notice that is really yours
The notice prints a date by which to file or respond, and the space for it is blank on the IRS's own sample — it is filled in per taxpayer. Use the date on your letter — there is no published day count, so that printed date is the one that governs.
There is a second date printed on a CP259 and it is the only thing on the notice that expires:
"Remember: if you are due a refund you must file within 3 years of the due date of the tax return, or within 2 years of the date the tax was paid."
Two things about where that sentence sits, and both matter. It is on the front page, inside the "If you are required to file" branch — not in the branch a reader who thinks they owe nothing will be reading. And it looks like boilerplate. It is not: for a business with deposits sitting against an unfiled period, it is the whole reason to act rather than wait. The balance the IRS is chasing may not exist; the money that does exist has a shelf life. The same point is printed twice more on page 4 of the form, in the notice's own words — "You must file a tax return in order to apply a carry forward credit even though you may not be required to file" and "You must file a tax return to be eligible for a refund even though you might not be required to file."
One limit on it that the notice does not print. A claim filed inside the three years still only recovers tax paid inside the applicable lookback period, so "in time" and "recovers everything" are different questions.
Neither date runs against the IRS. There is no time limit on assessing tax for a year in which no return was filed, which cuts the other way: the year does not go quiet on its own, and a business that waits is not running out anyone's clock but its own.
Which situation are you in?
Four, and the answer changes completely between them. This is the question the page exists to help you settle.
| Your situation | What the notice wants | What you send |
|---|---|---|
| The return is genuinely late | The return | Signed return plus the Response form |
| It was already filed | Proof | Response form with a signed, dated copy of the return, plus the EIN it was filed under |
| No return was required | A reason | Response form with the applicable box ticked |
| No return was required, but deposits were made | A return anyway | A signed return showing the payments, to recover them |
The fourth row is the trap and the IRS states it directly: "If you made federal tax deposits or other payments or credits for the tax period, you must file a signed return showing the payments to get a refund." "We had no employees" and "there is no money sitting there" are different questions, and the notice separates them even though nothing on it draws attention to the fact.
One more thing before you do anything: check the dates. "If you have filed within the last four weeks using the same name and EIN shown on the notice, you may disregard this notice." Notices and returns cross in the post more often than anyone would expect.
The five boxes, printed as the IRS prints them
Here are the "not required to file" boxes as printed on the IRS's own sample, page 4. They are the substance of this page and most guidance on CP259 does not mention that they exist. (The form has other blocks too — for a return already filed, for one filed late, and for credits and payments. This is the branch a reader who thinks they owe nothing is in.)
"If you don't think you have to file a tax return for the tax period ending on ____ — Explain why you don't think you are required to file a tax return for ____
My business ceased operations on: ___________
I had no employees during this period.
My business no longer has any employees and doesn't expect to pay wages in the future. Last date wages paid: ______________
I reported all wages on Form 943/944. (Please attach a signed copy of the Form 943/944 return).
Other reason for not filing (explain below; attach additional sheets if necessary)."
The third box is doing more work than it looks. It is not a statement about one quarter — it is a statement that no further wages are expected, which is how a closed employer stops the requirement rather than answering it quarter by quarter. Getting that box wrong is how a business that shut in 2023 is still receiving CP259s in 2026, one per quarter, each one answered individually and none of them closing the requirement.
And the fourth box is the one small employers most often need. A business that moved from quarterly Forms 941 to an annual Form 944, or that files a Form 943 for agricultural workers, has reported everything and still has an open 941 requirement on the record until somebody says so.
What happens if you do nothing
The consequence is printed on the notice and it is specific:
"If you don't file a tax return by ____ or dispute this notice, we may file a substitute return for you and charge penalty and interest on the amount of tax calculated."
A return the IRS prepares for a business is not a neutral estimate. It is built from what the IRS can see, which for an employer means wage information reported by other parties, and it allows nothing the business would have claimed for itself. The balance it produces is real, it is assessed, and it enters collection like any other.
One thing that a substitute return does not do, and it matters more than it sounds. A return prepared by the IRS in place of a taxpayer's own does not start the ordinary period the IRS has for assessing tax. Filing your own return is what starts that clock. A business waiting for the problem to age out is waiting for a clock that has not been switched on.
The other consequence is the one that has nothing to do with money. While a required return is missing, most of the arrangements a business would want — payment plans, penalty relief on other periods, a lien withdrawal — are unavailable. The unfiled period blocks the negotiation about every other period.
And if the missing returns are employment tax returns and the underlying deposits were also unmade, the account can stop being a filing problem and become a personal one — Letter 1153, and when payroll tax reaches an individual.

