How to Find Cardiologists by Zip Code

By the getdork research team — we build and maintain the NPI/physician-search tooling at getdork.com — Published June 12, 2026

Data sourced from live CMS NPI Registry API v2.1 queries, run June 12, 2026. All provider counts are real API responses, not estimates. Raw query results are available for download. See methodology below.

To find licensed cardiologists near a zip code, query the federal NPI registry with taxonomy_description=Cardiovascular+Disease — the exact CMS label for general cardiology. This returns names, NPI numbers, practice addresses, and phone numbers for providers who have registered with CMS in that area. This guide covers the correct taxonomy strings (including how subspecialties like interventional cardiology and electrophysiology are separate queries), real provider counts we retrieved from 9 markets, and how getdork automates the zip-radius math the public API cannot do.

Cardiology in the NPI registry: real counts from 9 markets

We queried the CMS NPI API v2.1 directly on June 12, 2026 for taxonomy_description=Cardiovascular+Disease across nine representative markets. The API returns a maximum of 200 records per request, so "200+" means the actual total exceeds 200 — the exact count is not available from this endpoint.

Market Query scope NPI records returned At 200-record cap?
New York, NY City filter 200+ Yes (more exist)
Los Angeles, CA City filter 200+ Yes (more exist)
Chicago, IL City filter 200+ Yes (more exist)
Houston, TX City filter 200+ Yes (more exist)
Phoenix, AZ City filter 200+ Yes (more exist)
Nashville, TN City filter 200+ Yes (more exist)
Memphis, TN City filter 162 No (complete)
Vermont (statewide) State filter 92 No (complete)
Wyoming (statewide) State filter 66 No (complete)

Source: CMS NPI Registry API v2.1, taxonomy_description=Cardiovascular+Disease, limit=200. Queried June 12, 2026. Counts include both individual providers (NPI-1) and organization records (NPI-2) such as cardiology group practices.

Why Memphis has a complete count but large metros don't: The API caps each response at 200 records regardless of true totals. For cities like New York or Houston, the 200-cap means the response is a partial sample only — there are more records than the API returns. For smaller cities and rural states, the full set fits within the cap, so the count is exact.

Cardiology subspecialties are separate taxonomy strings

This is the most important technical fact for anyone building a cardiology outreach list: the NPI registry uses five distinct taxonomy descriptions for the cardiology specialty group. A query for Cardiovascular Disease does not return interventional cardiologists or electrophysiologists — those are separate queries.

Subspecialty NPI taxonomy_description value NUCC code
General cardiologist Cardiovascular Disease 207RC0000X
Interventional cardiologist Interventional Cardiology 207RI0011X
Electrophysiologist (EP) Clinical Cardiac Electrophysiology 207RE0101X
Advanced heart failure / transplant Advanced Heart Failure and Transplant Cardiology 207RH0003X
Pediatric cardiologist Pediatric Cardiology 2080P0207X

In our June 2026 queries, both Interventional Cardiology and Clinical Cardiac Electrophysiology hit the 200-record national cap, confirming there are hundreds of providers registered under each subspecialty taxonomy. getdork lets you query multiple taxonomy strings in a single search session; the public API requires a separate request per taxonomy.

What the Memphis, TN results actually look like: Of the 162 records returned for Cardiovascular Disease in Memphis, 124 were true cardiologists (primary taxonomy: Internal Medicine, Cardiovascular Disease), 12 were interventional cardiologists, and the remaining 26 were records where another specialty was primary — including 10 general internists, 2 hospitalists, and 1 pediatric cardiologist. Individual providers (NPI-1) made up 116 records; 46 were organization records (NPI-2) for group practices and hospital departments. Credential breakdown: 102 MDs, 34 with credential listed as "M.D.", 1 D.O., 1 NP, and 55 records with no credential field filed.

How to search for cardiologists by zip code (5 steps)

Choose your search method

Two options access the same CMS database:

  • NPI registry directly at npiregistry.cms.hhs.gov — free, no account needed, but filters by city or state only. No radius search, no multi-taxonomy batching.
  • getdork Physician Search — same CMS API, with zip-code radius filtering (Haversine distance across 33,774 U.S. zip codes), the correct taxonomy string pre-mapped for each specialty, and CSV export.

Use the correct cardiology taxonomy string

For general cardiologists: taxonomy_description=Cardiovascular+Disease. The string "Cardiology" alone does not work — CMS uses the full phrase. The numeric taxonomy code (taxonomy=207RC0000X) is silently ignored by the API and returns unfiltered results.

If you need interventional cardiologists or electrophysiologists, those require separate queries with their own taxonomy strings (see the subspecialty table above). In getdork, selecting "Cardiology" from the dropdown handles the correct string automatically.

Enter your zip code and set a radius

Type the zip code at the center of your territory. In getdork, choose a radius in miles: 10, 25, 50, or 100. The tool identifies all U.S. zip codes within that radius using Haversine distance calculation against a dataset of 33,774 zip code centroids, then queries the NPI API for each matching zip.

The native CMS API filters by city or state, not radius. For a true geographic radius — for example, all cardiologists within 25 miles of a hospital zip code — you need either getdork or custom API batching code.

Run the search and interpret results

Each result includes: NPI number, provider name, credential (MD, DO, etc.), practice address, phone number, entity type (NPI-1 individual or NPI-2 organization), and the taxonomy description. Check the taxonomy field — a result set for Cardiovascular Disease will include some records where cardiology is a secondary taxonomy (see Memphis breakdown above).

Free accounts on getdork see the first 5 results per search. Pro accounts see all matches.

Export to CSV (Pro)

Pro users export the complete result set as a CSV with all fields. Column headers: NPI, Name, Credential, Address, City, State, Zip, Phone, Entity Type. The file includes a UTF-8 BOM for clean Excel import without re-encoding issues.

Querying the CMS NPI API directly

If you are building your own pipeline, here is the URL format. The taxonomy_description parameter is the only reliable specialty filter — the numeric taxonomy parameter is silently ignored by CMS NPI API v2.1. 

# General cardiologists in Memphis, TN — returned 162 records (June 2026)
https://npiregistry.cms.hhs.gov/api/?
  version=2.1
  &taxonomy_description=Cardiovascular+Disease
  &city=Memphis
  &state=TN
  &limit=200

# Interventional cardiologists only — separate taxonomy string required
https://npiregistry.cms.hhs.gov/api/?
  version=2.1
  &taxonomy_description=Interventional+Cardiology
  &city=Memphis
  &state=TN
  &limit=200

# Electrophysiologists (EP specialists) — another separate string
https://npiregistry.cms.hhs.gov/api/?
  version=2.1
  &taxonomy_description=Clinical+Cardiac+Electrophysiology
  &state=TN
  &limit=200

# Prefix wildcard catches all cardiology sub-taxonomies in one query
# Note: also returns non-cardiology matches where "Cardiovascular" appears
https://npiregistry.cms.hhs.gov/api/?
  version=2.1
  &taxonomy_description=Cardiovascular*
  &state=TN
  &limit=200

NPI record fields for cardiologists

Field What it contains Cardiology example
NPI 10-digit unique provider ID 1093014441
Name Provider first/last name (NPI-1) or organization name (NPI-2) John A. Smith, MD — or — Memphis Heart Group PC
Credential Degree / licensure abbreviation as filed with CMS MD, M.D., DO, MD PHD — or blank (55 of 162 Memphis records had no credential)
Practice address Primary practice location as filed with CMS 123 Heart Center Dr, Memphis, TN 38103
Phone Practice phone as filed with CMS (901) 555-0100
Entity type NPI-1 (individual provider) or NPI-2 (organization) 116 NPI-1 and 46 NPI-2 in the Memphis cardiology set
Taxonomy description CMS specialty label; may differ from the query string if cardiology is secondary Internal Medicine, Cardiovascular Disease
Enumeration date When the NPI was first assigned 2005-09-12
Radius search + subspecialty filtering, without writing API code.
getdork's Physician Search handles the NPI API calls, zip-radius math, and subspecialty taxonomy mapping. Free to preview results; Pro for the full set and CSV export.

Start free at getdork.com →

Frequently asked questions

What is the correct NPI taxonomy string to search for cardiologists?

The CMS taxonomy description for a general cardiologist is Cardiovascular Disease — not "Cardiology." Subspecialties are registered under entirely separate taxonomy strings: Interventional Cardiology, Clinical Cardiac Electrophysiology, Advanced Heart Failure and Transplant Cardiology, and Pediatric Cardiology each require their own query. A single Cardiovascular Disease search will miss interventional cardiologists and electrophysiologists unless you also run those subspecialty queries.

Why does a cardiology NPI search return non-cardiologist providers?

The NPI API returns records where Cardiovascular Disease appears anywhere in the provider's taxonomy list, not only as the primary specialty. In Memphis, roughly 14% of the 162 returned records had a different primary taxonomy — general internists, hospitalists, and a pulmonologist among them — with cardiovascular disease listed as a secondary credential. Filter on the taxonomies array in the JSON response if you need primary-specialty-only results.

How many cardiologists are in the NPI registry for a given market?

Based on live queries run June 12, 2026: Memphis, TN returned 162 records (complete set); Vermont statewide returned 92; Wyoming statewide returned 66. All six large metros we tested (New York, LA, Chicago, Houston, Phoenix, Nashville) hit the 200-record API cap, meaning the true totals are higher. The NPI API cannot return exact totals when a query exceeds 200 results — there is no pagination that reveals a grand total.

Why does the NPI API ignore the taxonomy code parameter?

CMS NPI API v2.1 silently ignores taxonomy=207RC0000X (the numeric NUCC code). Only taxonomy_description=Cardiovascular+Disease (the text label) filters results. Tools that pass numeric codes receive unfiltered provider results with no error or warning — a silent failure mode that produces bad data without any indication something went wrong.

What radius should I use for a cardiology territory search?

For major metros, 25 miles covers the city and close suburbs without spilling into neighboring cities. Rural markets like Wyoming have cardiologists spread over much larger distances — 50–100 miles may still return fewer than 30 providers. Dense urban cores (Manhattan, downtown Chicago) work at 5–10 miles because provider density is high enough. Match the radius to your actual sales or referral territory, not just the nearest cluster of providers.

Is the NPI registry free and how current is the data?

Yes — the CMS NPI registry is a public federal database, freely queryable at npiregistry.cms.hhs.gov with no authentication. getdork queries it live with no local cache. Data currency depends on providers filing updates with CMS — a provider who moved or retired may retain their old address until they update their CMS record. Each NPI record includes an enumeration date (when registered) and a last-update date; use those to gauge record freshness.

Data methodology

All provider counts in this article come from direct queries to the CMS NPI Registry API v2.1, run on June 12, 2026. We used the endpoint https://npiregistry.cms.hhs.gov/api/ with version=2.1, taxonomy_description=Cardiovascular+Disease (or subspecialty variants), and limit=200. No authentication token is required; this is a public API.

The API's result_count field in the response reflects records returned on that page, not a global total. When result_count equals 200 the actual total is unknown and exceeds 200. Counts that are below 200 are exact totals for that query.

Raw API responses for the Memphis, TN and Wyoming queries are saved alongside this article for independent verification. The PowerShell script used to collect all data is also available at _data/npi-counts-cardiology.ps1.

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