IRS Letters and Forms
CP83

CP83 — Campus notice only: issued when a math error is referred to Exam.

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

What to do next

Start with these steps before you reply.

CP83

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: issued when a math error is referred to Exam.

What it usually means

CP83 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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