What is John Brennan's NPI number?

John Brennan's National Provider Identifier (NPI) is 1891776977, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.

What is John Brennan's specialty?

John Brennan is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).

Where is John Brennan located?

John Brennan's practice location on file with NPPES is 191 Theater Rd, Onalaska, WI 54650.

What is John Brennan's phone number?

The practice phone number listed in the NPPES registry for John Brennan is (608) 785-0940.

Is John Brennan's NPI active?

Yes — John Brennan's NPI (1891776977) is active in the NPPES registry as of the last update on 2019-06-13.

IndividualActive

John Brennan, MD

NPI 1891776977 · Family Medicine Physician · Onalaska, WI

John Brennan, MD is a Family Medicine Physician provider in Onalaska, WI (NPI 1891776977).

Provider details

NPI number: 1891776977
Entity type: Individual
Primary specialty: Family Medicine PhysicianAllopathic & Osteopathic Physicians
Credential: MD
Sex: Male
Sole proprietor: No
License: 16368 (WI)

Specialties & taxonomies

Family Medicine PhysicianPrimary207Q00000XLicense 16368 (WI)
Allopathic & Osteopathic Physicians
Emergency Medicine Physician207P00000XLicense 16368 (WI)
Allopathic & Osteopathic Physicians
Emergency Medicine Physician207P00000XLicense 21682 (MN)
Allopathic & Osteopathic Physicians
Internal Medicine Physician207R00000XLicense 16368 (WI)
Allopathic & Osteopathic Physicians

Profile Score

Detailed profile(100/100 index)

A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.

Registry tenure38% of score
20 yrs in NPPES registry
Profile completeness38% of score
100% of core fields populated
Practice footprint23% of score
4 documented practice locations

Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.

Practice location

191 Theater Rd

Onalaska, WI 54650

Phone: (608) 785-0940

Approximate (ZIP-level) locationGet directions

More WI providers

Mailing address

Po Box 1510

Eau Claire, WI 54702-1510

Additional practice locations (3)

800 West Ave S
La Crosse, WI 54601-8806
Phone: (608) 785-0940
Fax: (608) 269-1010
325 Butts Ave
Tomah, WI 54660-1412
Phone: (608) 785-0940
325 Butts Ave
Tomah, WI 54660-1412
Phone: (608) 785-0940

Enumerated: 2005-11-07
Last updated: 2019-06-13

Frequently asked questions

What is John Brennan's NPI number?: John Brennan's National Provider Identifier (NPI) is 1891776977, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
What is John Brennan's specialty?: John Brennan is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
Where is John Brennan located?: John Brennan's practice location on file with NPPES is 191 Theater Rd, Onalaska, WI 54650.
What is John Brennan's phone number?: The practice phone number listed in the NPPES registry for John Brennan is (608) 785-0940.
Is John Brennan's NPI active?: Yes — John Brennan's NPI (1891776977) is active in the NPPES registry as of the last update on 2019-06-13.

Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.