Allergist access in the US, 2026

The largest metro areas

Among the 56 metro areas with 1,000,000 people or more, Boston-Cambridge-Newton, MA-NH has the most allergists per person (2.60 per 100,000) and Las Vegas-Henderson-North Las Vegas, NV the fewest (0.46). A clinician with offices in two metro areas counts in both.

Metro areas with no allergist

No allergist enrolled in Medicare lists a practice address in these 24 metro areas, home to 2.8 million people in all. People there may see one in a nearby area.

• Yakima, WA 259,000
• Kingston, NY 183,000
• Chambersburg, PA 161,000
• Lebanon, PA 146,000
• Hammond, LA 141,000
• Staunton-Stuarts Draft, VA 130,000
• Johnstown, PA 129,000
• Sierra Vista-Douglas, AZ 126,000
• Glens Falls, NY 124,000
• St. Joseph, MO-KS 119,000
• Michigan City-La Porte, IN 111,000
• Sebring, FL 111,000
• Gettysburg, PA 108,000
• Sumter, SC 105,000
• Victoria, TX 100,000
• Cape Girardeau, MO-IL 99,000
• Helena, MT 97,000
• Fairbanks-College, AK 94,000
• Parkersburg-Vienna, WV 87,000
• Great Falls, MT 85,000
• Casper, WY 81,000
• Lewiston, ID-WA 65,000
• Walla Walla, WA 62,000
• Eagle Pass, TX 59,000

How we counted

• The clinicians come from CMS’s Doctors and Clinicians file, updated October 2, 2026.¹ It is built from Medicare enrollment records and claims, with a 12-month claims lookback.²
• We count a clinician as an allergist when allergy/immunology is the primary or a secondary specialty in their Medicare enrollment. 3,576 list it as their primary specialty and 604 as a secondary one.
• The file has a row for each practice address.² We count a clinician once in each state and metro area where they have an address, and once in the US total.
• We place each address by its ZIP code, using the Census Bureau’s files that match ZIP code areas to counties⁷ (for Connecticut, its planning regions⁸) and counties to metro areas⁶. 33 ZIP codes, such as some for PO boxes, have no match; clinicians there count toward their state but not a metro area.
• We leave out clinicians whose NPI number is listed as deactivated in the national registry’s monthly report: 1 this time.³
• Rates use the Census Bureau’s population estimates for July 1, 2025.⁴⁵
• We publish counts only. We don’t name clinicians or keep their details.

What these numbers don’t show

• Allergists who aren’t enrolled in Medicare aren’t in the file, so they aren’t counted.
• Nurse practitioners and physician assistants in allergy practices count only if their own Medicare specialty is allergy/immunology.
• A count isn’t a measure of appointments: it doesn’t show waiting times, whether a clinician takes new patients or your insurance, or visits by telehealth.
• In places with few allergists, one practice opening or closing changes the rate a lot.

Sources

1. Doctors and Clinicians: National Downloadable File. Centers for Medicare & Medicaid Services.
2. Provider Data Catalog: Doctors and Clinicians Data Dictionary. Centers for Medicare & Medicaid Services.
3. NPI Files: monthly deactivation report. Centers for Medicare & Medicaid Services, NPPES.
4. State Population Totals and Components of Change: 2020-2025. U.S. Census Bureau.
5. Annual estimates of the resident population for metropolitan and micropolitan statistical areas, 2020-2025. U.S. Census Bureau.
6. Core based statistical areas and their counties, July 2023 (list 1). U.S. Census Bureau.
7. 2020 ZIP Code Tabulation Area to county relationship file. U.S. Census Bureau.
8. 2022 relationship files for Connecticut. U.S. Census Bureau.

How to cite

AllergyNest. “Allergist access in the US, 2026.” Data updated October 19, 2026. https://allergynest.com/reports/2026/allergist-access