Private Collection Agencies The law requires the IRS to use private agencies to collect certain outstanding, inactive tax debts. If your tax debt has been transferred to a private collection agency, you will be contacted by one of these four private collection agencies on the government's behalf: CBE P.O. Box 2217 Waterloo, IA 50704 800-910-5837 ConServe P.O. Box 307 Fairport, NY 14450 844-853-4875 Performant P.O. Box 9045 Pleasanton, CA 94566 844-807-9367 Pioneer PO Box 500 Horseheads, NY 14845 800-448-3531 How it works Before you are contacted by a private collection agency, you will receive two letters. The IRS will first send Notice CP40 and Publication 4518 PDF. These let you know that your overdue tax account was assigned to a private collection agency. The private collection agency then sends their initial contact letter. It has information on how to resolve your overdue taxes. Both letters contain a Taxpayer Authentication Number. It’s used to confirm your identity. It’s also for you to verify that the caller is legitimate. Keep this number in a safe place. What to do Work with your assigned private collection agency to resolve your overdue taxes. Questions and answers Get Transcript to verify the assignment of your account to a private collection agency Options to make Payments Watch for scams Reporting scams Report fraud, waste, & abuse What to expect after you receive a Notice You should validate that the caller is representing one of the private collection agencies listed above. The private collection agency will ask you a series of questions to make sure they’re talking to the correct person. You will be asked to exchange portions of the Taxpayer Authentication Number with the private collection agency to validate each other’s identity. The private collection agency will be courteous, professional and respect your taxpayer rights, while following the laws. The private collection agency will work with you to resolve your overdue taxes. They will NOT threaten you. If you feel the private collection agency acted inappropriately, here’s how to report it. For more information you can also view the IRS video Private Collection of Overdue Taxes.