Health insurance denial & claim adjustment codes

What health insurance denial code 27 means on your EOB

The plan says you were not covered on the date of service. Verify the termination date — retroactive terminations are common and frequently wrong.

What usually causes it

• Coverage terminated before the service date.
• A retroactive termination was applied.
• A premium payment was not posted.

The documents that decide it

• Your termination date per the plan.
• Your actual last day of coverage.
• Proof of premium payment.

What to do next

Retroactive terminations are restricted in many circumstances, especially in employer plans. Verify the date before accepting the denial.

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.