# CMS Medicare Ambulance Fee Schedule (AFS) Public Use File

`medicare_silver.fact_ambulance_fee_schedule` · Medicare Advantage, Part D, Medicaid · status live · 29,160 rows

The standalone CMS Medicare Ambulance Fee Schedule (AFS PUF) — per HCPCS (A0425-A0436 + mileage) × carrier × locality: RVU, GPCI, base rate, and urban/rural base + mileage rates. NOT inside PFS/OPPS/CLFS/DMEPOS/ASC; the reference benchmark for repricing ambulance claims (a top balance-billing / overpayment category). ~1.3k rows/year, CY2004-CY2026, partition by year; CY2004 is represented by two effective-period half-year vintages.

**Grain.** One row per (year, effective_period_start, effective_period_end, HCPCS × carrier × locality) — ambulance fee-schedule rates.

| column | type | meaning |
|---|---|---|
| year | int |  |
| row_seq | bigint |  |
| hcpcs | string |  |
| contractor_carrier | string |  |
| locality | string |  |
| rvu | double |  |
| gpci | double |  |
| base_rate | double |  |
| urban_base_or_mileage | double |  |
| rural_base_or_mileage | double |  |
| rural_base_lowest_quartile | double |  |
| rural_ground_miles_1_17 | double |  |
| observed_period | date |  |
| asserted_at | date |  |
| effective_period_start | date |  |
| effective_period_end | date |  |
| cms_vintage_sequence | int |  |
| parse_revision | int |  |
| parser_artifact_hash | string |  |
| source_url | string |  |
| sha256_content_hash | string |  |
| source_id | string |  |
| is_current | boolean |  |
| bronze_object_key | string |  |
| s3_version_id | string |  |
| vintage_tag | string |  |
| drug_source_version_id | string |  |

Query it: `query_substrate` with `SELECT ... FROM medicare_silver.fact_ambulance_fee_schedule WHERE ... LIMIT 100`; read `describe_data_source("medicare_silver.fact_ambulance_fee_schedule")` first.