William M. Ko, MD
Pain Medicine (Anesthesiology) Physician · Fullerton, CA
William M. Ko, MD is a pain medicine (anesthesiology) physician with a practice address in Fullerton, California, and NPI 1629011762, issued on Jun 14, 2006. Check the license (California A82916, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- William M. Ko
- Credential
- MD
- Primary taxonomy
- Pain Medicine (Anesthesiology) Physician 207LP2900X
- License number
- A82916 CA
Self-reported in NPPES; status is on the state search - Practice location
- 100 E Valencia Mesa Dr, Fullerton, CA 92835
- Phone
- (714) 446-5200
- Enumerated
- Jun 14, 2006
- Record last updated
- Nov 5, 2021 (not updated in 5 years: call before relying on the address or phone)
- Fax
- (714) 446-5292
- Medicare enrollment
- Enrolled (PECOS I20061219000259); accepts Medicare assignment
- Medical or professional school
- University Of Southern California Keck School Of Medicine, 2000
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest pain medicine (anesthesiology) physician records → All 536 in California → Look up another NPI →
Also registered at 100 E Valencia Mesa Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Jeffrey Bodwin, MDEndocrinology, Diabetes & Metabolism Physician1932195476
- Dennis Briley, PASurgical Physician Assistant1174731640
Verify William M. Ko in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A82916Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
37% more Medicare Part D claims than the average pain medicine (anesthesiology) physician in 2024
2,396 Medicare Part D claims for 411 beneficiaries, against an average of 1,750 among the 2,982 providers of this specialty who prescribed in Part D. Brand-name drugs were 3% of claims. 1,253 claims were for opioids.
Most prescribed
- Hydrocodone-Acetaminophen459 claims
- Gabapentin301 claims
- Oxycodone-Acetaminophen192 claims
- Meloxicam159 claims
- Morphine Sulfate Er142 claims
- Baclofen119 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.
Industry payments in 2024: $135.13
4 payments; by number, the most common kind was food and beverage; the largest payer was Biotronik Nro, Inc. The 2,789 providers of this specialty with any payment received $3,225.41 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 one group practice
- Providence Medical FoundationFullerton, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William M. Ko among 536 pain medicine (anesthesiology) physician records in California
William M. Ko, MD is one of 536 pain medicine (anesthesiology) physician records with a practice address in California. 83% 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 5% of them.
- NPI issued2006 · 5% of these records are older, 57% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 68% of these records are
- Graduated2000 · median 2004 among the 367 with a school on file
- Record last updated2021 · 51% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207LP2900X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Pain Medicine (Anesthesiology) Physician providers in California
There are 536 pain medicine (anesthesiology) physician records in California.
All 536 in California → Every provider in Fullerton → Pain Medicine (Anesthesiology) Physician nationwide →
The 8 pain medicine (anesthesiology) physician records with the nearest ZIP codes
- Jerry Fralick, M.D.Fullerton, CA 928351063408425
- Carl Hess, MDFullerton, CA 928351154471118
- Wei Kwok, M.D.Fullerton, CA 928351861430902
- Shveta Jain, M.D.Fullerton, CA 928311598024226
- Paul Le, MDAnaheim, CA 928071730251075
- Joon Sung, MDAnaheim, CA 928071891862611
- William Wang, MDAnaheim, CA 928071528130853
- Dennis Kuo, M.DAnaheim, CA 928051295140739
Common questions
What is William M. Ko, MD's NPI number?
William M. Ko, MD's National Provider Identifier (NPI) is 1629011762, issued on Jun 14, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William M. Ko, MD located?
The NPPES record lists a practice address at 100 E Valencia Mesa Dr, Fullerton, CA, 92835. Phone: (714) 446-5200. Providers update this record themselves, so call before visiting.
How can I verify William M. Ko, MD's license?
NPPES lists California license number A82916, 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. Ko, MD prescribe under Medicare Part D?
In 2024, William M. Ko, MD had 2,396 Medicare Part D claims for 411 beneficiaries; the average among pain medicine (anesthesiology) physician prescribers was 1,750. Part D covers Medicare prescriptions only.
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.