CP 108: Problem with your federal tax deposit: the IRS could not tell what an EFTPS payment was for

What CP 108 is

CP 108 "generates when the type of tax and/or tax period cannot be figured out on an Electronic Federal Tax Payment System (EFTPS) payment" (IRM 21.7.11.4.1(1), Oct. 1, 2025). It tells you where the credit was posted and encloses Form 15108, Correction to Your Federal Tax Deposit (FTD), to return if that posting is wrong. A common cause on Form 945 is a deposit keyed to Form 941 or to the wrong year in the YYMM tax-period field. If the payment landed on a form you do not file, the assistor transfers it and removes the filing requirement the keystroke created (IRM 21.7.11.4.1(2)).

The deadline

No printed deadline; reply "as soon as possible." A transfer is suspended when the correct return is due within two weeks of posting (IRM 21.7.11.4.1(2)).

What to do

Check the posting against your EFTPS confirmation. If it is right, do nothing; the manual says "There is no need to reply to the taxpayer" (IRM 21.7.11.4.1.4). If it is wrong, return Form 15108 or call the number on the notice with the correct EIN, tax form and period. The assistor's rule is "Always make any necessary credit transfers to move any incorrectly posted payments to the correct EIN, tax period, and MFT" (IRM 21.7.11.4.1.1(9)). Keep the CP 108 with your deposit records for the deposit-penalty computation.

How an EFTPS payment goes astray

Every EFTPS payment is tagged with three things in addition to the amount: the taxpayer's EIN, the tax form the payment is for, and the tax period in year-and-month form. A Form 945 deposit for backup withholding in 2026 is tagged as Form 945, period 2612, because Form 945 is an annual return and the period is the December of the year. The most common mistakes are keying Form 941 instead of 945 (the payroll return the same person deposits for every two weeks), entering the current month as the period so the deposit lands on a year that does not exist yet for an annual form, or, when a payroll provider makes the deposit, using the wrong EIN. EFTPS accepts the payment as tagged. When the tag does not resolve to a return the IRS expects from you, or resolves to a period that makes no sense, the IRS posts the money where the tag points and issues CP 108 to tell you where it went, with Form 15108 attached for you to correct it.

Payments can be cancelled in EFTPS up to two business days before the settlement date, but not after; once settled, only the IRS can move the credit.

Fixing it, and why speed matters for Form 945

Compare the posting shown on the CP 108 with your EFTPS confirmation and your deposit schedule. If the notice is right (the payment really was for the form and period shown), nothing is required. If it is wrong, return Form 15108 or call the number on the notice and give the correct EIN, form and period; the IRS moves the credit as of the original payment date, so a deposit that was timely when made stays timely once transferred. The reason to act quickly is the failure-to-deposit penalty: until the credit is moved, the Form 945 account shows the deposit as missing, and when the return posts the account will compute a penalty on the shortfall. If the correct return is due within two weeks of the posting, the IRS holds the transfer until the return is in. Keep the CP 108, the Form 15108 and the EFTPS record together; if a deposit penalty does issue on the 945, they are the evidence that the money was paid on time to the wrong tag, which is the standard ground for removing it. The Form 945 page covers the deposit schedule, and the deposit penalty calculator shows what a misposted deposit costs if it is not corrected.

Questions about CP 108

Have a different notice? The IRS notice decoder lists all 77 in the order they tend to arrive.