Medicare Compliance/Intermediate/18 minutes/Reviewed 2026-07-10

Medicare Timely Filing: The One-Year Rule

Calculate the general Original Medicare filing deadline and distinguish a late original claim from an adjustment or reopening.

Quick answer

Original Medicare generally requires a claim to reach the correct contractor no later than 12 months, or one calendar year, after the applicable date of service. A timely-filing denial is generally not an initial determination and is not appealable.

Rules to know

Use the applicable service date rule for professional or institutional claims.
Keep submission and acknowledgment evidence.
Do not confuse an original late claim with adjustment or reopening rules.
Do not automatically transfer a provider-caused late balance to the beneficiary.

Operational workflow

01Identify the applicable from or through date.
02Calculate one calendar year and verify contractor receipt, not only transmission.
03Review any documented statutory exception before writing off.
04If a timely claim needs correction, evaluate adjustment or reopening rules.
05Document the final disposition and beneficiary-liability basis.

Common failure modes

Using payer upload date instead of contractor receipt evidence.
Filing to the wrong payer and noticing after the deadline.
Calling a non-appealable timely-filing denial a medical-necessity appeal.

Knowledge check

What generally controls the Medicare deadline?

The date the claim was createdReceipt by the correct contractor within one calendar yearThe date the patient statement printedThe appeal date

Official sources

Medicare Claims Processing Manual, Chapter 1 - General Billing RequirementsCenters for Medicare & Medicaid ServicesReviewed 2026-07-10 Medicare Billing: 837P and Form CMS-1500Medicare Learning NetworkReviewed 2026-07-10

Continue this track

IntermediatePrior Authorization Workflow and Denial Prevention AdvancedMedicare Secondary Payer and Coordination of Benefits AdvancedABNs and GA, GY, GZ, GX Modifiers

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