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CP166
CP166 — Informs taxpayer of a default on a Direct Debit Installment Agreement (DDIA) due to insufficient funds. DDIA payments ar…
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CP166
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
Informs taxpayer of a default on a Direct Debit Installment Agreement (DDIA) due to insufficient funds. DDIA payments are electronic payments and not subject to an IRC 6657 bad check penalty charge.
What it usually means
CP166 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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