How long do I have to respond to IRS CP40?

Verify the assigned agency. Check the date and any response deadline printed on your notice, and follow the notice's instructions.

What should I do if I received IRS CP40?

Unpaid tax account assigned to a private collection agency. Verify the assignment and review your options. If you are unsure, have a tax professional review the letter before you respond to the IRS.

IRS CP40 Notice: Account Assigned to a Private Collection Agency

The IRS assigned your unpaid tax account to a private collection agency. Verify the agency and review your payment options.

Editorially reviewed by the Law Offices of Darrin T. Mish, P.A.Updated October 1, 2026

Notice: CP40
Urgency: Attention
Deadline: Verify the assigned agency

Your first move

Unpaid tax account assigned to a private collection agency. Verify the assignment and review your options.

CP40 tells you that the IRS assigned your unpaid tax account balance to a private collection agency. The notice identifies the agency and provides information for verifying the assignment.

Verify the Agency

Keep the notice. The assigned agency will also send a confirmation letter. Use the agency information and Taxpayer Authentication Number on your CP40 to complete the two-party verification process described by the IRS before discussing your account.

Review Your Options

Check the balance against your records. If you can pay in full, use an official IRS payment method. If you cannot, ask the assigned agency about a payment plan. If you dispute the debt or need help evaluating your options, have a tax professional review your account.

Source: IRS guidance for CP40. Reviewed October 1, 2026.

For help understanding your notice, call (813) 229-7100.

Want a second set of eyes on this letter?

Free consultation with Darrin T. Mish, a Tampa tax attorney licensed since 1993 and admitted to the U.S. Tax Court. Bring the letter.

Call (813) 229-7100

Request a consultation online