John Thomas Halloran, DO
Internal Medicine Physician · Sacramento, CA
John Thomas Halloran, DO is an internal medicine physician with a practice address in Sacramento, California, and NPI 1851888697, issued on Apr 17, 2018. Check the license (California 20A19224, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- John Thomas Halloran
- Credential
- DO
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 20A19224 CA
Self-reported in NPPES; status is on the state search - Practice location
- 3000 Q St FL 3, Sacramento, CA 95816
- Phone
- (916) 733-3400
- Enumerated
- Apr 17, 2018
- Record last updated
- Jan 18, 2022
- Fax
- (916) 733-5384
- Medicare enrollment
- Enrolled (PECOS I20220111001870); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 3000 Q St FL 3
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify John Thomas Halloran in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A19224Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
71% fewer Medicare Part D claims than the average internal medicine physician in 2024
934 Medicare Part D claims for 156 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 16% of claims.
Most prescribed
- Atorvastatin Calcium105 claims
- Amlodipine Besylate77 claims
- Lisinopril60 claims
- Levothyroxine Sodium38 claims
- Metformin Hcl33 claims
- Losartan Potassium31 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The MIPS final score for 2023 (Medicare payment program): 96.5 of 100
The Merit-based Incentive Payment System score is reported for this clinician. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Community Medical Centers, Inc.Lodi, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
John Thomas Halloran among 17,696 internal medicine physician records in California
John Thomas Halloran, DO is one of 17,696 internal medicine physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2018, is newer than 84% of them.
- NPI issued2018 · 84% of these records are older, 14% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2018 · median 2004 among the 11,065 with a school on file
- Record last updated2022 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
601 internal medicine physician records list a practice address in Sacramento
They are 601 of the 33,083 NPPES records with a practice address in Sacramento, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Sacramento → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Michael Abate, MDSacramento, CA 958161548248131
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- Lisa Ho, M.D.Sacramento, CA 958161932184108
- John Hosoume, M.D.Sacramento, CA 958161588649354
- James Jackson, MDSacramento, CA 958161508855594
- Ingvild Lane, MDSacramento, CA 958161831171719
- Scott Macdonald, MDSacramento, CA 958161518940006
Common questions
What is John Thomas Halloran, DO's NPI number?
John Thomas Halloran, DO's National Provider Identifier (NPI) is 1851888697, issued on Apr 17, 2018. An NPI identifies a provider in billing; it is not a license.
Where is John Thomas Halloran, DO located?
The NPPES record lists a practice address at 3000 Q St FL 3, Sacramento, CA, 95816. Phone: (916) 733-3400. Providers update this record themselves, so call before visiting.
How can I verify John Thomas Halloran, DO's license?
NPPES lists California license number 20A19224, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does John Thomas Halloran, DO prescribe under Medicare Part D?
In 2024, John Thomas Halloran, DO had 934 Medicare Part D claims for 156 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is John Thomas Halloran, DO's MIPS final score?
The 2023 MIPS final score is 96.5 of 100. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.