CARC code B15 — Service/procedure requires a qualifying service/procedure to be received first

What CARC B15 means

Prior authorization denials mean the service required your insurer's pre-approval and either it wasn't obtained, it was denied, or proof of it is missing.

How to appeal a CARC B15 denial

Appeals in this category typically succeed when you can document that the prior-auth process was attempted, that urgent circumstances prevented it, or that the service should be covered as an exception. A treating-provider letter is the single most important supporting document.

What InsureDefense adds

Our triage classifies your specific denial into one of ten categories and tells you exactly what evidence appeals like yours typically need. For CARC B15 denials, we usually recommend the tier that fits the category of the denial — sometimes Strong ($249) is enough, sometimes Premium ($499) with plan-language citations and peer-reviewed support is the right path. The free triage shows you which.

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