Wrong dates on medical bills, and why they cost you

The quietest source of medical billing error is dates, because a wrong date almost never looks wrong.

Four different dates appear on the documents you get: the service date, the statement date, the posting date, and the date the claim was processed. They mean entirely different things, and mixing them up produces problems that look like benefit decisions.

The example above is common around a job change. Coverage under the old plan ended June 30. The service happened July 9. The claim went to the old plan anyway, and the denial that came back looked like a coverage decision when it was really an eligibility problem. The fix was to have the provider resubmit the claim to the plan that was in force on the date of service.

What to check:

• Every service date sits inside the coverage period you are checking, anchored on the service date and never on the date the invoice was issued.
• No claim has been sitting in pending or in review for more than about 45 days.
• You are working from the newest version of an EOB, not one that has been superseded.

Two gaps worth watching for as well: a claim with real patient responsibility where you never received a bill, and a claim that arrived with no line detail at all. You cannot check either one, and the discipline is to record them as unchecked rather than assume they are fine. An unverifiable claim is not a clean claim.

Whenever you write to anyone, cite the service date. It is the one date all three parties agree on.

General information, not legal, medical or financial advice. Every plan is different, so check the details against your own plan documents.