CP59, CP259, CP518 and CP518B: IRS Unfiled Return Notices

One family, two tracks

IRS.gov's page on notices for past due tax returns lists the whole family together: CP59, CP259, CP515, CP516, CP518 and CP518B, plus CP63, CP2566, CP2566R and CP3219N, which have their own page. Read the first six as two escalation ladders that share a notice number, CP518, for their final reminder.

The individual ladder starts with the CP59, which IRS.gov describes as telling you the IRS has no record you filed your prior personal tax return or returns. The business ladder starts with the CP259, sent when the IRS shows a required business return for the periods on the notice has not been filed. Both use the same logic: a filing requirement is on the IRS's books, no return has posted, and a notice goes out.

If your notice carries a different number, it may be the Spanish-language version. IRM 5.19.2 refers to "the Spanish IMF CP 616 or 618" as counterparts to the CP516 and CP518, and IRM 5.19.22 lists the CP959 as the Spanish version of the CP259 and the CP618 as the Spanish version of the CP518. The individual CP59 is paired in the IRM with a CP759, but the IRM text read for this page does not label it as Spanish, so this page does not say what it is.

The individual track: CP59, CP515, CP516, CP518

The Internal Revenue Manual (IRM 5.19.2) says the CP59 goes out on selected delinquent individual accounts and that a CP518 will generally follow if no return posts, or the delinquency is not otherwise closed, within eight weeks of the CP59. The account can then move to a more serious delinquency status six weeks after the CP518.

CP515 and CP516 are the two notices that do not fit the simple ladder. The IRM says a CP515 is issued when a CP59 is returned undelivered with a new address, and the CP59 is reissued. IRS.gov's CP515 page instead describes it as a reminder that the IRS still has no record of your return. This page reports both descriptions and does not reconcile them, because the sources do not.

For CP516, IRS.gov says it reminds you that a previous notice went unanswered and the IRS still has no record of the return. The IRM adds that accounts it codes as primary code "B" receive two notices, the CP59 and the CP516, and stay at that stage; the IRM's own statement of that group's path ends there.

Whichever of the four you hold, the response IRS.gov describes is the same: file the return with a completed Form 15103, Form 1040 Return Delinquency, explaining why you are filing late or that you already filed, or complete Form 15103 alone to explain why you do not have to file. If you are only sending the form to say you did not need to file, IRS.gov says it can be submitted online through an IRS Online Account. IRS.gov also says the IRS accepts electronic returns for the two most recent prior years, through an e-file provider that offers it.

The CP518 is the one IRS.gov labels a final reminder, and its page states the consequence of silence directly: the IRS may determine your tax for you, penalty and interest may continue to accrue, and a refund you are owed may be delayed because of the unfiled return. The CP59 page is milder but makes the same point about time limits: if you do not file, you may lose your claim to a refund or certain credits, and penalties and interest continue to accrue until you file and pay in full.

The business track: CP259 and CP518B

For business returns, IRM 5.19.22 says a delinquent return is picked up 16 weeks after its due date, and a CP259 is the first notice. Its packet includes a Letter 3164 (third-party contact notice), a Notice 609 (Privacy Act notice) and a return envelope. If the delinquency is not resolved, the IRM says a CP518 generally follows about 10 weeks after the CP259, and if that goes unresolved, the case can move on to Collection enforcement or an IRS-prepared return under IRC 6020(b).

IRS.gov's CP259 page tells you to file the required business return, electronically with all required schedules if you are eligible or on paper otherwise. If you believe you are not required to file, complete the Response form in the packet. If you filed within the last four weeks under the same name and EIN, IRS.gov says you can disregard the notice.

IRS.gov's CP518B page is a business final reminder, and it is a different page from the individual CP518. It says to send a signed paper return with all required schedules and to return the Response form, explaining either why you are filing late, why you believe you do not need to file or already filed, or that you filed under a different name or EIN than the one on the notice. Documents can go back in the enclosed envelope or by fax to the number on IRS.gov. If the IRS does not hear from you, IRS.gov says it may determine your tax for you, penalty and interest can continue to accrue, and refunds for the current or any prior year may be delayed.

One caution about "just filed." IRS.gov's CP259 and CP518B pages say four weeks in the main text. The FAQ on the CP518B page says eight. If you are near the edge of either window, answering costs you a stamp and not answering is the risk.

What a CP515B search gets confused with: the CP515 and the CP518B

People search for "CP515B," and it is not a notice the IRS names. It does not appear on IRS.gov's list of past due return notices, and the word does not occur anywhere in IRM 5.19.2 (individual return delinquency) or IRM 5.19.22 (business return delinquency). Some sites use the name anyway, but this site holds it as unverified until the IRS itself publishes a page or IRM text that names it.

What does exist, and looks like it, is the CP515 (individual reminder) and the CP518B (business final reminder). If your notice came addressed to an EIN and calls itself a final reminder, it is most likely the CP518B described above. If it came addressed to your Social Security number, it is one of the individual notices. The notice itself prints its number, so read it before you assume.

Before you respond

IRS.gov's pages give the same preparation steps across the family. Check that the name, Social Security number (or EIN) and tax year on the notice match what is on your return. Review your own records to confirm you filed every prior return, and if a copy is missing, IRS.gov points to downloadable blank copies of prior year returns and forms. To rebuild income you cannot document, IRS.gov points to its transcript services, which provide the income information the IRS holds about you; an account transcript can be read with the Account Transcript Analyzer if you want to see what the IRS shows on the account.

If you are a federal employee or retiree and the notice arrived alongside or after an LT36 letter, the two are separate mailings about the same underlying problem, an unfiled return or an unpaid balance, and answering the unfiled-return notice does not answer an unpaid balance.

Help is available if the situation is more tangled than a missed filing. Each of the six IRS.gov pages says you can authorize someone to represent you before the IRS, and points to the Taxpayer Advocate Service and, where you qualify, to a Low Income Taxpayer Clinic. If you cannot resolve the notice on your own, those are the routes IRS.gov names.

What each response does and does not do

Filing the return, or sending the response form, is what these notices ask for. It does not pay a balance. IRS.gov says penalties and interest continue to accrue until you file and pay in full, and the penalty calculator can estimate them. If you cannot pay in full, the FAQ on each of the six notice pages points to a payment plan, and an installment agreement is the usual route.

Ignoring the notice moves the account along the ladders above: first notice, final reminder, then a status change and, for businesses, Collection enforcement or a return the IRS prepares itself. IRS.gov notes that even when the IRS files a substitute return, it is still in your interest to file your own to take advantage of the exemptions, credits and deductions you are entitled to.

The other notices on the same IRS page

IRS.gov's past due returns page also lists four notices this page does not cover; they have their own page, CP63, CP2566, CP2566R and CP3219N. CP63 says the IRS is holding a refund because you have not filed one or more returns and it believes you will owe tax. CP2566 and CP3219N say the IRS did not receive your return and has calculated tax, penalty and interest from wages and other income reported by employers and others. CP2566R is the follow-up to a CP63 that drew no reply, with the same calculation. Those describe a refund hold or an IRS-calculated amount rather than only a request to file, so a notice that shows a calculated balance is a different problem from the ones above.

Where this comes from

Every statement here traces to IRS.gov's notices for past due tax returns page, its six per-notice pages (linked in the citations below), IRM 5.19.2 and IRM 5.19.22. The timing statements (eight weeks, six weeks, ten weeks, sixteen weeks) are the IRM's own and carry its "generally" qualifier: they describe the normal system flow, and an individual account can be moved faster or held longer.

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