IRS Letters and Forms
CP01B

CP01B — Message about potential Identity Theft during return processing.

Message about potential Identity Theft during return processing.

What to do next

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CP01B

Read the notice carefully and note any deadline. Gather returns, notices, and payment records. Book a free strategy session before responding if the amount is large, unclear, or collection language appears.

What the IRS language says

Message about potential Identity Theft during return processing.

What it usually means

CP01B is in our IR Manual catalog. Official wording is dense — we translate it for business owners and individuals and map realistic next steps.

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