What this notice is about
We received your Form 2848, Power of Attorney and Declaration of Representative, Form 8821, Tax Information Authorization, or Form 706, U.S. Estate Tax Return, authorizing you to act or receive information on a taxpayer’s behalf. Because of this, we assigned you a Centralized Authorization File (CAF) number.
What you need to do
Use your CAF number on future authorizations and when contacting the IRS about a taxpayer you represent.
You may want to
- Keep your CAF number in a safe place for future reference.
- Notify the IRS if this was assigned without your knowledge.
Frequently asked questions
What is a CAF number? (updated Mar. 27, 2026)
It’s a unique nine-digit identification number you’re assigned the first time you file a third-party authorization with the IRS.
What if I already have a CAF number? (added Mar. 27, 2026)
If you’re assigned more than one CAF number that you didn’t request, send us a copy of each CP547 using the fax number listed on your notice. Protect yourself when sending digital data. Understand your fax service’s privacy and security policies.
What should I do if I don’t remember my CAF number? (updated Mar. 27, 2026)
Call Practitioner Priority Services (PPS) at 866-860-4259. PPS service hours are weekdays 7 a.m. to 7 p.m. local time. Alaska and Hawaii follow Pacific time. Puerto Rico service hours are 8 a.m. to 8 p.m. local time.
Once you’re verified, your CAF number can be provided over the phone. If we can’t verify you, we’ll send a letter to the representative’s address on file.
Herramientas de referencia
- Publicación 1 (SP), Derechos del Contribuyente
- Publicación 594 (sp), El Proceso de Cobro del IRS PDF
- Publicación 1660 (SP), Derechos para la Apelación de Cobros PDF
- Aviso 746, Información Sobre su Aviso, Multas e Intereses PDF
- Pago de impuestos
- Lista completa de formularios y publicaciones tributarios (en inglés)
¿Necesita ayuda?
- Puede autorizar a alguien para comunicarse con el IRS en su nombre.
- Vea si califica para recibir ayuda de una Clínicas para Contribuyentes de Bajos Ingresos.
- Si no puede encontrar lo que necesita en línea, llame al número del IRS que se indica en la parte superior de su carta o aviso. Si no recibió una carta o aviso, utilice la asistencia telefónica.
- Si no puede resolver la multa por su cuenta, comuníquese con el Servicio del Defensor del Contribuyente, una organización independiente dentro del IRS.