IRS Letters and Forms
CP170

CP170 — Campus only notice : that a duplicate return tried to post from a TC 370 (doc. code 51)

Campus only notice : that a duplicate return tried to post from a TC 370 (doc. code 51)

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CP170

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 only notice : that a duplicate return tried to post from a TC 370 (doc. code 51)

What it usually means

CP170 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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