William M. Webster, M.D
Emergency Medicine Physician · Marysville, CA
William M. Webster, M.D is an emergency medicine physician with a practice address in Marysville, California, and NPI 1669412714, issued on Jun 7, 2006. Check the license (California A66945, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- William M. Webster
- Credential
- M.D
- Primary taxonomy
- Emergency Medicine Physician 207P00000X
- License number
- A66945 CA
Self-reported in NPPES; status is on the state search - Practice location
- 726 4TH Street, Marysville, CA 94901
- Phone
- (530) 749-4300
- Enumerated
- Jun 7, 2006
- Record last updated
- Nov 21, 2007 (not updated in 19 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20090120000260); accepts Medicare assignment
- Medical or professional school
- University Of Oklahoma College Of Medicine, 1994
- Entity
- Type 1 · individual
8 nearest emergency medicine physician records → All 7,751 in California → Look up another NPI →
Also registered at 726 4TH Street
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Mark Agness, M.D.Family Medicine Physician1609816743
- Pamela Fallo, C.F.N.PRegistered Nurse1689612921
- Katherine Kelly, N.PFamily Nurse Practitioner1679517205
- Robert Martin, M.DEmergency Medicine Physician1205876208
- Robert Olson, P.A-CPhysician Assistant1932147287
- Steven Segerstrom, M.DFamily Medicine Physician1205876240
Verify William M. Webster in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A66945Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
50% fewer Medicare Part D claims than the average emergency medicine physician in 2024
114 Medicare Part D claims for 82 beneficiaries, against an average of 226 among the 54,106 providers of this specialty who prescribed in Part D. 16 claims were for opioids.
Most prescribed
- Prednisone18 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): 94.6 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: $180.16
7 payments; by number, the most common kind was food and beverage; the largest payer was Abbvie Inc. The 12,335 providers of this specialty with any payment received $953.79 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.
Bills Medicare through 2 group practices
- Cep America - CaliforniaRoseville, CA
- Vituity-California Observation Services PCRoseville, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William M. Webster among 7,751 emergency medicine physician records in California
William M. Webster, M.D is one of 7,751 emergency medicine physician records with a practice address in California. 81% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 4% of them.
- NPI issued2006 · 4% of these records are older, 60% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 59% of these records are
- Graduated1994 · median 2011 among the 4,560 with a school on file
- Record last updated2007 · 59% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207P00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
12 emergency medicine physician records list a practice address in Marysville
They are 12 of the 708 NPPES records with a practice address in Marysville, and 7,751 emergency medicine physician records in California.
All 7,751 in California → Every provider in Marysville → Emergency Medicine Physician nationwide →
The 8 emergency medicine physician records with the nearest ZIP codes
- Robert Martin, M.DMarysville, CA 949011205876208
- Kulwinder Singh, M.DMarysville, CA 949011396782934
- George Williams, M.DMarysville, CA 949011629012810
- Mather Neill, M.DGreenbae, CA 949021073612537
- Morgan Camp, MDSan Rafael, CA 949031407845738
- Cynthia Clark, MDSan Rafael, CA 949031144219767
- John David, MDSan Rafael, CA 949031912081993
- Anna Denham, MDSan Rafael, CA 949031750465738
Common questions
What is William M. Webster, M.D's NPI number?
William M. Webster, M.D's National Provider Identifier (NPI) is 1669412714, issued on Jun 7, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William M. Webster, M.D located?
The NPPES record lists a practice address at 726 4TH Street, Marysville, CA, 94901. Phone: (530) 749-4300. Providers update this record themselves, so call before visiting.
How can I verify William M. Webster, M.D's license?
NPPES lists California license number A66945, 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 William M. Webster, M.D prescribe under Medicare Part D?
In 2024, William M. Webster, M.D had 114 Medicare Part D claims for 82 beneficiaries; the average among emergency medicine physician prescribers was 226. Part D covers Medicare prescriptions only.
What is William M. Webster, M.D's MIPS final score?
The 2023 MIPS final score is 94.6 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.