Specialties / Endocrinology

Medicare specialty 46 · #41 of 83 by enrollment

Endocrinology: Medicare enrollment by state

8,405 NPIs are enrolled in Medicare as endocrinology (provider type 14-46), number 41 of 83 practitioner specialties. The most are in California (928), then New York (884). As a share of each state's Medicare-enrolled NPIs, the specialty is largest in New York (0.5%) and smallest in Wyoming (0.1%). Another 327 are enrolled in the same specialty only to order and refer, not to bill.

24JNPI1234567893207RE0101XEndocrinology1234
  1. 1Enrolled NPIs 8,405
  2. 2Most in California
  3. 3Taxonomy codes mapped 1
  4. 4Medicare specialty code 46
California928New York884Texas661Florida574Massachusetts445New Jersey399Pennsylvania392Illinois369Ohio334North Carolina251Georgia232Michigan221
Endocrinology: Medicare-enrolled NPIs in the 12 states with the most, bars to scale. Source: CMS PPEF, 2026-09-29.

Taxonomy codes for endocrinology

CMS's crosswalk maps 1 NUCC taxonomy code to Medicare specialty 46. A provider enrolling as endocrinology should hold one of them as the primary taxonomy on their NPI.

CodeName
207RE0101XEndocrinology, Diabetes & Metabolism Physician

Where it is concentrated

Raw counts follow population, so the more telling figure is each state's share: what fraction of the state's Medicare-enrolled NPIs are endocrinology. Nationally the specialty is 0.3% of enrolled NPIs. The highest shares are in New York (0.5%), Massachusetts (0.5%), New Jersey (0.5%); the lowest in Wyoming (0.1%), Alaska (0.1%), North Dakota (0.1%). 51 of the 51 (50 states and DC) have at least one enrolled.

Billing versus order-and-refer enrollment

Medicare enrolls practitioners in two ways. A full enrollment lets the provider bill Medicare for their own services; it is what the 8,405 above count. An order-and-refer-only enrollment lets a provider who never bills Medicare — a resident, a VA or military physician, a dentist ordering imaging — still order tests, equipment and referrals that Medicare pays for. 327 endocrinology NPIs hold that limited enrollment.

Every state

Counts are unique NPIs enrolled in each state; a provider enrolled in two states counts in both. The share is of all Medicare-enrolled NPIs in that state.

StateEnrolledShare of state
California9280.4%
New York8840.5%
Texas6610.3%
Florida5740.3%
Massachusetts4450.5%
New Jersey3990.5%
Pennsylvania3920.3%
Illinois3690.3%
Ohio3340.3%
North Carolina2510.3%
Georgia2320.3%
Michigan2210.2%
Virginia2100.3%
Maryland2060.4%
Missouri1970.4%
Wisconsin1810.3%
Washington1780.3%
Minnesota1760.3%
Connecticut1760.4%
Indiana1740.3%
District of Columbia1690.3%
Tennessee1500.2%
Colorado1430.2%
Arizona1420.2%
South Carolina1030.2%
Alabama920.2%
Louisiana900.2%
Oregon880.2%
Kentucky870.2%
Iowa700.2%
Kansas680.2%
West Virginia670.3%
Mississippi650.3%
Oklahoma590.2%
Nevada570.2%
Nebraska540.3%
New Hampshire510.3%
Arkansas480.2%
New Mexico410.2%
Delaware380.3%
Utah380.2%
Maine360.2%
Rhode Island290.2%
Hawaii290.2%
South Dakota270.3%
Vermont220.2%
Idaho180.1%
Montana170.1%
North Dakota120.1%
Alaska70.1%
Wyoming70.1%

Sources: CMS Medicare Fee-For-Service Public Provider Enrollment, extract of 2026-09-29; CMS Medicare Provider and Supplier Taxonomy Crosswalk, August 2026. Checked 2026-10-24. Methodology.