M86 remark code

Remittance advice remark code M86. Remark codes add detail to the reason code on the same claim line.

Similar service already paid recently

Unofficial reference. This is our own plain-English explanation, not the official code text. Payer rules differ. Verify with the payer and the official X12 code list. AlphaPrefix is not affiliated with X12, CMS or any payer. Data last updated Nov 11, 2026.

What M86 means

The payer limits how often this kind of service is paid and found a matching or similar one already paid inside that window.

The payer limits how often this service can be paid and found an earlier paid claim, from you or another provider, inside that window. It is a frequency limit rather than a duplicate claim match.

It often appears with reason code 119 or 151. The time frame differs by service and payer, so check the policy.

Common causes

• The service was repeated before the payer's frequency limit allowed.
• Another provider billed the same service for the patient within the period.
• A replacement item or repeat test was medically needed but not documented as such.

What to do next

1. Find the date of the earlier paid service if the payer shows it.
2. Check the payer's frequency rule for the service.
3. If an exception applies, appeal with documentation showing why the repeat was necessary.
4. Review any advance notice before deciding who is responsible for the balance.

Related codes

• 119 (reason code) Benefit maximum reached
• M3 (remark code) Same or similar equipment already in use
• M80 (remark code) Not payable alongside an earlier service