Medicare (Original) Payer ID
- Payer ID
- MAC-specific
- Category
- Government
- Timely filing
- 12 months — see Medicare (Original) filing rules →
Payer IDs can differ between clearinghouses (Availity, Waystar, Office Ally, Trizetto, etc.) and by product line. Confirm this ID against your clearinghouse's payer list before submitting.
Routing notes for billers
Original Medicare has no single payer ID — claims route to your regional MAC (Novitas, Noridian, Palmetto, WPS, NGS, CGS, FCSO) and each MAC jurisdiction has its own ID in your clearinghouse. Search your payer list for the MAC name plus your state.
If claims to this payer go missing
Misrouted claims surface as CO-109 denials or remark N418 — and meanwhile the filing clock keeps running. Keep your clearinghouse acceptance reports as proof of original submission; they usually restart the clock on appeal.
OakClaim routes every claim right the first time.
Free audit shows how much misroutes and rejections are costing your practice.