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CP310 notice: what it means and what to do
Got an IRS CP310 notice? Here is what it means, your deadline, what to check before you answer, and how to reply. Check your own letter free: it stays on your phone.
Check my CP310 notice freeWhat the IRS says this notice is about
We assigned you a Personal Identification Number (PIN) to associate your existing Centralized Authorization File (CAF) number through Tax Pro Account for identity assurance.
You don't need to call or respond to this notice.
What you need to do
Use the PIN number to verify your identity and complete your request:
- Sign in to Tax Pro Account .
- Associate your CAF number to your personal information by entering your PIN.
Your deadline
Answer by the date printed on your notice. If there is no date, answer as soon as you can, and call the number on the notice if you need more time.
What to check before you answer
Verify your identity before the date
Use the online service or phone number printed on your letter. Have the letter, your tax return for that year, and the one for the year before. Your return is not processed until you verify.
Is this letter really from the IRS?
The IRS writes first by mail. A real letter shows a notice or letter number, your name and part of your tax ID number. The IRS does not ask for payment by gift card, crypto or wire transfer. If in doubt, sign in to your IRS online account, where many notices are listed.
You may want to
- Keep your PIN in a safe place for your records.
- Call the IRS number at the top of your notice if you didn't request a PIN or if you have questions.
Important things to remember about your PIN
- It can only be used to verify ownership of your CAF number in Tax Pro Account and will expire in 30 days.
- It is unique to your CAF number.
- It is for your use only. Keep it secure and don't share it with anyone.
Helpful information
- Find how to submit Form 2848, Power of Attorney and Declaration of Representative or Form 8821, Tax Information Authorization to a taxpayer's online account with Tax Pro Account .
- Read more about CAF Authorization Rules .