What Happens After an 837P Claim Is Submitted?

Technical acknowledgment comes first

A receiving system may first report whether the electronic transaction or functional group could be processed structurally.

Claim acknowledgment can follow

A claim acknowledgment such as a 277CA can report claim-level acceptance or rejection status before adjudication.

Accepted is not paid

An accepted claim can still later be denied, adjusted, or paid differently based on coverage, coding, eligibility, medical necessity, authorization, or other adjudication rules.

Keep the response files

Save acknowledgment files with the original submission. They can help identify which file, transaction, or claim needs correction and resubmission.

Sources and verification

• CMS: Medicare Billing — CMS-1500 & 837P
• CMS Electronic Billing & EDI Transactions