What Your Insurer Means by "Not Medically Necessary"

The letter is designed to sound final. It is not final, and it is not what it appears to be.

“Not medically necessary” is a phrase with an administrative meaning, and the administrative meaning is narrow: the documentation submitted did not match the plan’s written criteria for that service. A reviewer read a file against a rulebook. Nobody examined anyone. In most of the denials I have worked through, the treating clinician and the plan do not actually disagree about the patient — they disagree about whether a form said the right thing in the right field.

That is good news, because paperwork problems have paperwork solutions.

Ask for three things, in writing

The full denial letter, including the specific criterion cited. Many households only ever see a summary — an explanation-of-benefits line, or a portal notification. Request the complete determination.

The plan’s coverage criteria for that service. You are entitled to the rule you were judged against. Ask for it by name: the medical policy or coverage determination for the service and the plan year.

The claim file. What was actually submitted, including codes. A surprising share of denials are a coding mismatch, and you cannot see that from the outside.

Ask in writing, keep the date, and keep a copy. In the households I have worked with, “in writing” is what turns a phone conversation nobody logged into a record somebody has to answer — the same discipline that makes a discharge go well.

Write to the criteria, not about the patient

This is the part that goes wrong most often, and it goes wrong for a sympathetic reason. Families write letters about the person. The letters are true, and they are moving, and they lose.

The appeal that works is boring. It takes each criterion in the plan’s own document and answers it, with the documentation attached, in the plan’s own vocabulary. The person best placed to write it is not you: it is the treating clinician’s office, specifically whoever handles prior authorisations, and asking for their help explicitly — “can you write to the criteria in the medical policy?” — gets a different and better response than asking them to “help with an appeal.”

The deadline is the whole game

Every denial letter carries a clock. It usually starts on the date printed on the letter, not the day the letter reached your kitchen table, and I have watched households lose four days to the mail and another two to a weekend.

Diary it the day it arrives. If the documents you need have not turned up in time, file a holding letter that says an appeal is coming and asks for the clock to be acknowledged. It is a small piece of paper that preserves everything.

After the internal levels, most plans lead to an independent external review, conducted outside the insurer. Households routinely stop before that point, usually out of exhaustion. It is a different set of eyes, it is free to the patient in most arrangements, and reaching it is a matter of not missing the step before it.

What this piece is not

It is not medical advice and there is nothing in it about treatment. What is being contested in an appeal is not usually clinical anyway — it is whether the paperwork met a written standard, which is exactly the sort of fight a household can prepare for, and exactly the sort that households abandon because the letter was written to sound like the end of a conversation.

It is the beginning of one.