IRS Letters and Forms
CP123

CP123 — Math error, overpayment or balance due of less than $1 on Form CT-1

Math error, overpayment or balance due of less than $1 on Form CT-1

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CP123

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

Math error, overpayment or balance due of less than $1 on Form CT-1

What it usually means

CP123 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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