IRS Letters and Forms
CP64

CP64 — Campus notice only: Notice of Tentative Carryback Allowance.

What this IRS notice code means, and what to check before you reply.

What to do next

Start with these steps before you reply.

CP64

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

Campus notice only: Notice of Tentative Carryback Allowance.

What it usually means

CP64 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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