Anesthesiologists Information Center
Access CMS anesthesiology resources, including Medicare payment policies, anesthesia conversion factors, billing guidance, and participation requirements.
Announcements
Resources
Enrollment & Participation
- Medicare Provider-Supplier Enrollment
- Nineteen states chose to opt-out of the certified registered nurse anesthetists physician supervision regulation - See Spotlight
Coverage
Policies, Regulations & Legislation
- Title 42 - Public Health, Chapter IV CMS/DHHS: Conditions of Participation:
- Part 482.52 - Anesthesia Services
- Part 410.69 - Services of a certified registered nurse anesthetist or an anesthesiologist's assistant: Basic rule and definitions
- Pharmaceutical Services - 482.25 (Title 42 - Public Health, Chapter IV CMS/DHHS)
- Title 42 - Public Health, Chapter IV CMS/DHHS: Conditions of Participation:
Coding
Program Manuals & Transmittals
- Medicare Claims Processing Manual
- Appendix A of the State Operations Manual, pages 31-35 (PDF): See Anesthesia Services - Appendix A (482.52)
- Medicare Claims Processing Manual (Chapter 12 Physician/Nonphysician Practitioners)(PDF): (See Sub-Section K, p. 111 for information on Anesthesia Claims Claims Modifiers) contains the amount physicians and other providers will receive when providing services to a Medicare beneficiary
- Transmittals
Billing & Payment
Anesthesia conversion factors used to compute allowable amounts for anesthesia services under CPT codes 00100 to 01999
| Anesthesia Conversion Factors Files | Notes | Update Date |
|---|---|---|
| 2026 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for CY 2026 | 12/29/2025 |
| 2025 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for CY 2025 | 12/26/2024 |
| 2024 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for CY 2024 | 03/14/2024 |
| 2023 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for CY 2023 | 01/06/2023 |
| 2022 Anesthesia Conversion Factors (ZIP) | 12/20/2021 | |
| 2022 Anesthesia base units by CPT code (ZIP) | These are the anesthesia base units used to compute allowable amounts for anesthesia services under CPT codes 00100 to 01999 | |
| 2021 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for CY 2021 | 12/29/2020 |
| 2020 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for CY 2020 | |
| 2019 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for CY 2019 | |
| 2018 Anesthesia Conversion Factors (ZIP) | ||
| 2018 Anesthesia Base Units by CPT Code (ZIP) | These are the anesthesia base units used to compute allowable amounts for anesthesia services under CPT codes 00100 to 01999 | |
| 2017 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for 2017 | |
| 2016 Anesthesia Conversion Factors (ZIP) | The anesthesia base units are unchanged for 2016 | |
| 2015 Anesthesia Conversion Factors (July 1- Dec 31) (ZIP) | The anesthesia base units are unchanged for 2015 | |
| 2015 Anesthesia Conversion Factors (Jan 1 – June 30) (ZIP) | The anesthesia base units are unchanged for 2015 | 01/06/2015 |
| 2014 Anesthesia Conversion Factors (ZIP) | 01/03/2014 | |
| 2014 Anesthesia Base Units by CPT Code (ZIP) | These are the anesthesia base units used to compute allowable amounts for anesthesia services under CPT codes 00100 to 01999 | |
| 2013 Anesthesia Conversion Factors (ZIP) | 12/31/2012 | |
| 2013 Anesthesia Base Units by CPT Code (ZIP) | These are the anesthesia base units used to compute allowable amounts for anesthesia services under CPT codes 00100 to 01999 | |
| 2012 Anesthesia Conversion Factor 0% Update (ZIP) | 03/01/2012 | |
| 2012 Anesthesia Base Units by CPT Code (ZIP) | These are the anesthesia base units used to compute allowable amounts for anesthesia services under CPT codes 00100 to 01999 | |
| 2011 Anesthesia Conversion Factor (ZIP) | 04/02/2012 | |
| 2011 Anesthesia Base Units by CPT Code (ZIP) | These are the anesthesia base units used to compute allowable amounts for anesthesia services under CPT codes 00100 to 01999 | |
| 2010 Anesthesia Conversion Factor 0% update and 2010 Anesthesia Conversion Factor 2.2% update | ||
| 2010 Anesthesia Base Units by CPT Code (ZIP) | These are the anesthesia base units used to compute allowable amounts for anesthesia services under CPT codes 00100 to 01999 | |
| 2009 Anesthesia Conversion Factor (ZIP) |
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Page Last Modified:
07/01/2026 12:05 PM