Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
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John R. Gregory, MD

Individual provider Surgery Physician · NPI 1861504847

John R. Gregory, MD practises General Surgery in Billings, Montana. Graduated from University of Colorado School of Medicine, Denver in 1975, 51 years ago. Practices with Billings Clinic, a 805-clinician group and accepts Medicare assignment. Licensed in Montana.

Years since qualifying
51
Trained at
University of Colorado School of Medicine, Denver
Licensed in
MT
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

801 N 29th St
Billings, MT 59101-0905
Phone: (406) 238-2500
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Surgery Physician (primary) Taxonomy 208600000X · Licence 4284 (MT)

Record details

NPI number1861504847
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedAugust 31, 2006
Last updated in NPPESFebruary 10, 2022
Certification dateFebruary 10, 2022

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyGENERAL SURGERY
Medical schoolUNIVERSITY OF COLORADO SCHOOL OF MEDICINE, DENVER
Graduated 1975 (51 years in practice)
Group practice Billings Clinic — 805 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations2 on file with Medicare

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Spinal fusion 15 times · 32nd percentile
Upper gastrointestinal (GI) endoscopy for acid reflux 1–10 times

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients115
Services billed 222 a service is one billed item, such as a visit, a test or a procedure
Average patient age73

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Billings Clinic

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 805 clinicians in the practice; 12 are shown here.

Other providers in Billings