Medicare Gives You Twelve Months. Most Practices Use Two.

Medicare allows one calendar year from the date of service to file a claim. Compared with commercial windows that can be a fraction of that, it feels like room to breathe. That feeling is where the problem starts.

The complacency pattern

Because the window is long, Medicare claims that fall out of the normal flow do not create urgency. A claim held for missing documentation, or denied and parked, sits without alarm. Commercial claims in the same state get attention because their deadline is visibly near.

So aged Medicare A/R accumulates quietly — and then a batch of it crosses twelve months at once, because the claims that stalled all stalled around the same time for the same reason.

What the window does and does not cover

Twelve months is for the initial claim. It is not the appeal deadline, which is shorter and runs from the determination rather than the date of service. Practices conflate the two and assume they have a year to appeal a denial. They do not.

Reopening a claim for a clerical error is a different mechanism again, with its own timeframe, and it is not a substitute for a timely appeal.

The practical controls

• Report Medicare A/R by date of service, not posting date. The filing clock runs from service.
• Set an internal deadline well inside the external one — a claim unfiled at ninety days needs a reason, not a year of grace.
• Track appeal deadlines separately from filing deadlines. They are different clocks measuring different things.

A twelve-month window is a safety margin, not a schedule. Practices that treat it as a schedule discover the difference all at once.