Notice decoder
Start with the code on your letter.
Normalize a notice-code format and check whether it appears in the public directory.
Code only — don’t enter personal tax information.
Enter only a notice code, such as CP504. Do not enter your name, Social Security number, address, or other personal details.
No explanation is generated for unrecognized codes
If a code is not in the directory, this preview will not guess. Unknown searches are not submitted or saved.