providerfile
Taxonomy 302R00000X
HEALTH MAINTENANCE ORGANIZATION4,594 ON THE REGISTER195

Health Maintenance Organization

4,594 active US providers register Health Maintenance Organization as their primary taxonomy. That is 0.05% of every provider in the registry, and the 195th largest of 584 specialties with a page here.

Taxonomy code
302R00000X
Grouping
Managed Care Organizations
Classification
Health Maintenance Organization
Active providers
4,594
States covered
51 of 51

What the code means

(1) A form of health insurance in which its members prepay a premium for the HMO's health services which generally include inpatient and ambulatory care. For the patient, an HMO means reduced out-of-pocket costs (i.e. no deductible), no paperwork (i.e. insurance forms), and only a small copayment for each office visit to cover the paperwork handled by the HMO; (2) A organization of health care personnel and facilities that provides a comprehensive range of health services to an enrolled population for a fixed sum of money paid in advance for a specified period of time. These health services include a wide variety of medical treatments and consults, inpatient and outpatient hospitalization, home health service, ambulance service, and sometimes dental and pharmacy services. The HMO may be organized as a group model, an individual practice association (IPA), a network model or a staff model.

Definition quoted verbatim from the NUCC Health Care Provider Taxonomy code set, version 25.1. Not paraphrased.

Where they are

Counted by practice location, not by mailing address or by licence state. A provider practising across a state line is counted where they practise.

Showing the 15 largest of 51 states with at least one.

Who registers under this code

286 of these are people and 4,308 are organisations, so 94% of the code is businesses rather than clinicians. Half of them had registered by 2012, and 528 registered in the last five years, 11% of the current population.

That is a slow-growing code, which usually means an established field replacing retirements rather than expanding.

Where the practices are

By practice-location city. City counts are noisier than state counts, because a large employer files one address for many providers.

What else they list

Providers whose primary code is Health Maintenance Organization most often carry these secondary taxonomies as well. This is the closest thing the registry has to a map of which specialties overlap in practice, and it is not published anywhere else.

Looking up a specific provider

These counts come from the monthly NPPES file. To check one provider, use their NPI: the lookup reads the live registry and shows whether the identifier is still active, which the monthly file cannot tell you about the last few weeks.

Counts from npidata_pfile_20050523-20260712.csv, built 2026-08-09. Primary taxonomy only, deactivated identifiers excluded.