Crossover Claims: Why the Secondary Never Arrived

When a Medicare patient has supplemental coverage, the claim is supposed to cross over automatically — Medicare processes, then forwards the balance to the secondary. When it works it is invisible. When it fails it is also invisible, which is the problem.

How the failure presents

A balance remains after Medicare pays. Nothing indicates whether the secondary was billed and denied, billed and pending, or never billed at all. In most aging reports it looks like an ordinary outstanding balance, and in some workflows it gets reclassified as patient responsibility and sent to the patient.

That last outcome is the worst version: a patient with valid supplemental coverage receives a bill for something their plan would have paid.

Why crossover breaks

• The supplemental is not on file with Medicare, or is recorded with stale details.
• The patient changed plans and the coordination record still shows the old one.
• The plan is not part of the automatic arrangement, so it never crosses and must be billed directly.
• Identifiers mismatch between what Medicare holds and what the secondary expects.

Catching it

The remittance tells you whether a claim crossed. If it did, there is a defined waiting period before the secondary responds, and chasing earlier is wasted effort. If it did not, the claim must be billed directly, and the secondary's own filing window is running from a date you may not be watching.

The control worth having

A report of Medicare claims with a remaining balance and no secondary payment after the expected interval. That single view separates "waiting" from "never sent", which is the distinction the aging report cannot make and the one that decides whether the balance is workable or already lost.