IRS / Tax Error Code

CP503 | Second balance due reminder

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IRS / Tax

Canonical

/irs-tax/error-codes/cp503-notice/

Last Updated

Apr 16, 2026

Summary

CP503 is a follow-up balance due reminder indicating the IRS has not received payment for an outstanding amount.

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What This Code Means

CP503 is a follow-up balance due reminder indicating the IRS has not received payment for an outstanding amount.

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