John P. Williams, D.O.
Internal Medicine Physician · Willits, CA
John P. Williams, D.O. is an internal medicine physician with a practice address in Willits, California, and NPI 1144220369, issued on Jul 29, 2005. Check the license (California 20A6027, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- John P. Williams
- Credential
- D.O.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 20A6027 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1712 S Main St, Willits, CA 95490
- Phone
- (707) 459-5585
- Enumerated
- Jul 29, 2005
- Record last updated
- Dec 19, 2018 (not updated in 8 years: call before relying on the address or phone)
- Fax
- (707) 459-3548
- Medicaid ID
- 00AX60271 CA
- Medicare enrollment
- Enrolled (PECOS I20050718000819); accepts Medicare assignment
- Medical or professional school
- University Of New England, College Of Osteo Medicine, 1989
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
Verify John P. Williams in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A6027Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
3.7 times the Medicare Part D claims of the average internal medicine physician in 2024
11,847 Medicare Part D claims for 389 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 13% of claims. 1,060 claims were for opioids.
Most prescribed
- Atorvastatin Calcium442 claims
- Amlodipine Besylate429 claims
- Gabapentin399 claims
- Hydrocodone-Acetaminophen377 claims
- Levothyroxine Sodium305 claims
- Oxycodone Hcl277 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 practice group's MIPS final score for 2023 (Medicare payment program): 73.8 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. 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, group reporting; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $546.49
26 payments; by number, the most common kind was food and beverage; the largest payer was Bayer Healthcare Pharmaceuticals Inc. The 50,334 providers of this specialty with any payment received $1,303.06 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
5 internal medicine physician records list a practice address in Willits
They are 5 of the 162 NPPES records with a practice address in Willits, and 17,696 internal medicine physician records in California.
All 5 in Willits → All 17,696 in California → Every provider in Willits →
Other internal medicine physician records in California
- Jacob Aaron, MDSan Francisco, CA1407202518
- Alistair Aaronson, MDStanford, CA1457628760
- Jose Abad., MDSacramento, CA1144607219
- Donna Abare, MDOakland, CA1386722155
- Marce AbareScotts Valley, CA1457744708
- Samuel Abarte, M.D.Chula Vista, CA1578535498
- Alexander Abary, MDLong Beach, CA1104995919
- Luba Abascal, MDSan Francisco, CA1023180874
- Michael Abate, MDSacramento, CA1548248131
- Wali Abawi, D.O.Joshua Tree, CA1104362268
Common questions
What is John P. Williams, D.O.'s NPI number?
John P. Williams, D.O.'s National Provider Identifier (NPI) is 1144220369, issued on Jul 29, 2005. An NPI identifies a provider in billing; it is not a license.
Where is John P. Williams, D.O. located?
The NPPES record lists a practice address at 1712 S Main St, Willits, CA, 95490. Phone: (707) 459-5585. Providers update this record themselves, so call before visiting.
How can I verify John P. Williams, D.O.'s license?
NPPES lists California license number 20A6027, 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 P. Williams, D.O. prescribe under Medicare Part D?
In 2024, John P. Williams, D.O. had 11,847 Medicare Part D claims for 389 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is John P. Williams, D.O.'s MIPS final score?
The 2023 MIPS final score is 73.8 of 100, reported for the practice group. 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.