CMS ZIP code to carrier locality files, release by release
The quarterly crosswalk mapping every 5-digit ZIP code to the Medicare payment locality whose GPCIs price claims from that ZIP.
Jumps straight to the locality this ZIP maps to.
CMS updates this file quarterly—January, April, July, and October—and occasionally re-posts a quarter mid-stream to fix errors. Each version we ingested is preserved below as its own immutable release.
CMS reorganizes its site often and direct file links break. If a download link below stops working, every release remains available from the official CMS ZIP-to-locality crosswalk page.
2026 Copy link
In effect October 1 – December 31, 2026 (Q4 2026 on this site).
In effect July 1 – September 30, 2026 (Q3 2026 on this site).
In effect April 1 – June 30, 2026 (Q2 2026 on this site).
In effect January 1 – March 31, 2026 (Q1 2026 on this site).
2025 Copy link
In effect July 1 – September 30, 2025 (Q3 2025 on this site).
In effect April 1 – June 30, 2025 (Q2 2025 on this site).
In effect January 1 – March 31, 2025 (Q1 2025 on this site).
2024 Copy link
In effect July 1 – September 30, 2024 (Q3 2024 on this site).
In effect April 1 – June 30, 2024 (Q2 2024 on this site).
In effect January 1 – March 31, 2024 (Q1 2024 on this site).
2023 Copy link
In effect October 1 – December 31, 2023 (Q4 2023 on this site).
2022 Copy link
In effect April 1 – June 30, 2022 (Q2 2022 on this site).
In effect January 1 – March 31, 2022 (Q1 2022 on this site).
2021 Copy link
In effect July 1 – September 30, 2021 (Q3 2021 on this site).
In effect April 1 – June 30, 2021 (Q2 2021 on this site).
In effect January 1 – March 31, 2021 (Q1 2021 on this site).
2020 Copy link
In effect July 1 – September 30, 2020 (Q3 2020 on this site).
In effect April 1 – June 30, 2020 (Q2 2020 on this site).
In effect January 1 – March 31, 2020 (Q1 2020 on this site).
2019 Copy link
In effect July 1 – September 30, 2019 (Q3 2019 on this site).
In effect April 1 – June 30, 2019 (Q2 2019 on this site).
In effect January 1 – March 31, 2019 (Q1 2019 on this site).
2018 Copy link
In effect July 1 – September 30, 2018 (Q3 2018 on this site).
In effect April 1 – June 30, 2018 (Q2 2018 on this site).
In effect January 1 – March 31, 2018 (Q1 2018 on this site).
Our methodology documents how every file is parsed, versioned, and verified.