Reference documentation
Data & sources.
What FeeBase supports, where rates come from, and how to interpret a result.
What the lookup supports
- Schedule
- CMS Medicare Physician Fee Schedule base participating rates.
- Service date
- The accepted releases listed below determine available dates. End dates are exclusive; future releases apply only to their stated periods.
- Geography
- CMS ZIP-to-locality mappings and Geographic Practice Cost Indices. Some ZIPs need ZIP+4 to resolve a locality.
- Settings
- Facility and non-facility base rates. Reference pages and the basic lookup use the unmodified code entry. The contract checker can select supported modifier-specific source rows; it does not model every modifier rule. 2025 uses a single schedule; 2026 distinguishes QP and non-QP schedules.
- Release availability
- The list below reflects accepted source data. Each release applies to its stated period; future updates require import validation and acceptance.
- Geography fallback
- When the requested period has no accepted ZIP file, the lookup may use the most recent earlier accepted mapping. Results explicitly label that earlier release.
What a reference rate means
Follow a real calculation and inspect its source rows →
The Medicare amount is a base participating Physician Fee Schedule reference: geographically adjusted relative value units multiplied by the applicable conversion factor, rounded to cents.
It is before claim adjustments. It is not a practice’s charge, a commercial contracted rate, a guaranteed payment, or a patient estimate. The “your rate” column applies your selected percentage to that reference; it does not predict reimbursement.
Accepted source releases
The releases below power the lookup. Effective dates identify the period each file covers; the original CMS archive is linked alongside it.
Swipe to see dates and sources →
| Dataset | Release | From | Until (exclusive) | Source |
|---|---|---|---|---|
| Physician Fee Schedule | RVU26D | 2026-10-01 | 2027-01-01 | CMS source |
| ZIP geography | ZIP2026Q4 | 2026-10-01 | 2027-01-01 | CMS source |
| Physician Fee Schedule | RVU26C | 2026-07-01 | 2026-10-01 | CMS source |
| Physician Fee Schedule | RVU26B | 2026-04-01 | 2026-07-01 | CMS source |
| ZIP geography | ZIP-2026B | 2026-04-01 | 2026-07-01 | CMS source |
| Physician Fee Schedule | RVU26A | 2026-01-01 | 2026-04-01 | CMS source |
| ZIP geography | ZIP-2026A | 2026-01-01 | 2026-04-01 | CMS source |
| Physician Fee Schedule | RVU25D | 2025-10-01 | 2026-01-01 | CMS source |
| ZIP geography | ZIP2025D | 2025-10-01 | 2026-01-01 | CMS source |
| Physician Fee Schedule | RVU25C | 2025-07-01 | 2025-10-01 | CMS source |
| ZIP geography | ZIP-2025C | 2025-07-01 | 2025-10-01 | CMS source |
| Physician Fee Schedule | RVU25B | 2025-04-01 | 2025-07-01 | CMS source |
| ZIP geography | ZIP-2025B | 2025-04-01 | 2025-07-01 | CMS source |
| Physician Fee Schedule | RVU25A | 2025-01-01 | 2025-04-01 | CMS source |
| ZIP geography | ZIP2025 | 2025-01-01 | 2025-04-01 | CMS source |
Known limits
Only supported active-code calculations return an amount. Unsupported status codes, OPPS caps, unavailable settings, missing rate rules, and unresolved geography return an explicit status rather than a zero or estimated rate.
This lookup does not adjudicate claims, apply every modifier or claim adjustment, determine coverage, or calculate patient responsibility. Use the CMS source and applicable payer rules for your decision.
Found a discrepancy?
Include the code, location, service date, and selected settings. Please don’t send patient information.
Report a rate issue