Health insurance denial & claim adjustment codes

What health insurance denial code 284 means on your EOB

You have an authorization number and the plan says it does not cover this particular service, date, or provider. Usually a mismatch between what was approved and what was billed.

What usually causes it

• The authorization named a different procedure code.
• The service happened outside the approved date range.
• A different provider or facility performed the care.

The documents that decide it

• The authorization letter with approved codes, dates, and providers.
• The claim as submitted.
• Any documented change in provider or facility.

What to do next

Line up the authorization against the claim. Mismatches are often clerical and correctable without a formal appeal.

This page explains what a code means. It is information, not advice — it does not tell you whether your specific claim should have been paid, and it is not legal, medical, or insurance advice. Your plan documents and your denial notice govern your situation.