RemitBench/Denial codes/M86

M86 remark code

M86 points at a specific earlier payment rather than at a count. Something the payer considers the same or similar was already paid for inside a window, and this claim fell inside it.

The code list's own wording: Service denied because payment already made for same/similar procedure within set time frame.

Why the payer sent it

• The same procedure was genuinely performed and paid inside the window.
• A different but related procedure was paid, and the payer treats them as equivalent.
• Another provider performed the earlier service.
• The earlier claim was for a different tooth or site and the detail did not carry.
• A claim was resubmitted and paid twice, so the history is wrong.
• The window is longer than you assumed.

The reason codes it rides with

What to do next

1. Ask which earlier claim the payer is pointing at

   Date, procedure and provider. Without those three facts there is nothing to check and nothing to argue.

   If it is a different tooth or site: that is a strong reprocessing request, and it usually means the detail on one of the two claims did not carry. If it is your own claim resubmitted: the history is duplicated. Name the claim numbers.

2. Decide whether "similar" is fair

   This is the appeal, if there is one. Two procedures the payer groups together are not always clinically equivalent, and explaining the difference is a real argument rather than a plea.

3. Find out how long the window is

   Windows vary widely, and practices often assume a year where the plan means several. The number matters for planning the next case as much as for this one.

Codes that get mixed up with M86

The useful split: 18 says identical, M86 says similar, and N640 says too many. Only the middle one rests on a judgment you can argue with.

M86 in dental

This is the replacement rule remark. Crowns, dentures, bridges and other restorations carry minimum intervals, and M86 is how a payer says the previous one is still inside its window.

The previous dentist's work counts

A crown placed by a previous practice starts the clock and the patient usually does not remember the year. The carrier does. On any replacement case, asking for the date of the previous restoration before treatment turns a denial after the fact into a financial conversation before it.

Similar is broader than identical

Payers group restorations that a practice would treat as clinically different. A large restoration and a crown on the same tooth can be treated as similar, and so can different crown materials. Where you think the grouping is wrong, saying exactly why is the appeal.

Questions people ask about M86

What counts as a similar procedure?

The payer decides, and its grouping is often broader than a practice would expect. Different crown materials, or a large restoration and a crown on the same tooth, can be treated as similar. Ask which earlier claim the payer is pointing at, because that is the only way to tell whether the grouping is reasonable.

Is M86 worth appealing?

More often than a plain frequency limit, because it rests on a judgment that two services are equivalent. If the earlier service was a different tooth, a different site, or genuinely a different procedure, explaining that is a real argument.

Related codes

• N640 Exceeds the number or frequency allowed. A count rather than a specific payment.
• CO-18 Exact duplicate claim or service.
• CO-97 Included in payment for another service.
• N130 Read the plan document. Where the window is written down.

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