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Your IRS CP566 Notice, Explained
Also called: Notice CP566, CP 566, ITIN Additional Information Notice
Last reviewed 2026-07-12
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What this notice usually means
A CP566 notice means the IRS needs more information to process your Form W-7 application for an Individual Taxpayer Identification Number, called an ITIN. This usually happens because a form was incomplete or a document was missing or did not meet the IRS's rules for acceptable proof. The notice and its response form list exactly what to send back. You have 45 days from the date on your notice to reply. The IRS decides whether to issue the ITIN.
See every source line for this notice
“We need more information to process your application for an individual taxpayer identification number (ITIN)”
“You may have sent us an incomplete form.”
“You may have sent us the wrong documents.”
“Send us the documents we've asked for when you reply.”
What to do now
- 1
Reread your ITIN application instructions
Make sure you truly need an ITIN. You may already qualify for a Social Security number instead.
- 2
Review every question on your application
Check that you answered every question. Make sure your documents match what the form asks for.
- 3
Send the exact documents your notice requests
Use documents that are not expired and show your photo, like a passport, visa, or state ID.
- 4
Translate foreign-language documents if asked
If your notice asks for a translation, use a certified translator. Send the translation with your documents.
- 5
Complete and mail the response form
Sign the response form at the end of your notice and mail it with your documents within 45 days of the date on your notice.
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You have 45 days from the date on your notice to reply with the requested documents and response form.
“You have 45 days from the date of your notice to reply”
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Sources
- Internal Revenue Service (IRS.gov)Retrieved 2026-07-12
Last reviewed 2026-07-12
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