Warren Woo, M.D.
Family Medicine Physician · Placentia, CA
Warren Woo, M.D. is a family medicine physician with a practice address in Placentia, California, and NPI 1447340336, issued on Oct 13, 2006. Check the license (California C40927, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Warren Woo
- Credential
- M.D.
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License number
- C40927 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1275 N Rose Dr, Placentia, CA 92870
- Phone
- (714) 961-1635
- Enumerated
- Oct 13, 2006
- Record last updated
- Sep 30, 2011 (not updated in 15 years: call before relying on the address or phone)
- Fax
- (714) 961-1679
- Medicare enrollment
- Enrolled (PECOS I20081025000011); accepts Medicare assignment
- Medical or professional school
- University Of Texas Medical Branch At Galveston, 1980
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 17,133 in California → Look up another NPI →
Also registered at 1275 N Rose Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Pauline Ho, M.D.Specialist1194854794
- Ali Houshyar, MDInternal Medicine Physician1568434595
- Peter Kwon, M.D.Internal Medicine Physician1003840471
- John Marshburn, M.D.Ophthalmology Physician1245246164
- Melanie Reed, D.P.M.Podiatrist1427034370
- Kenneth Schemmer, M.D.Specialist1619066867
Verify Warren Woo in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license C40927Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
53% fewer Medicare Part D claims than the average family medicine physician in 2024
1,677 Medicare Part D claims for 280 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. Brand-name drugs were 14% of claims. 24 claims were for opioids.
Most prescribed
- Atorvastatin Calcium101 claims
- Rosuvastatin Calcium96 claims
- Losartan Potassium80 claims
- Levothyroxine Sodium56 claims
- Metoprolol Succinate56 claims
- Amlodipine Besylate50 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): 76.3 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: $152.68
2 payments; by number, the most common kind was food and beverage; the largest payer was Lilly USA, LLC. The 55,478 providers of this specialty with any payment received $902.55 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
- Pih Health PhysiciansLa Habra, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Warren Woo among 17,133 family medicine physician records in California
Warren Woo, M.D. is one of 17,133 family 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 6% of them.
- NPI issued2006 · 6% of these records are older, 59% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 62% of these records are
- Graduated1980 · median 2005 among the 10,652 with a school on file
- Record last updated2011 · 58% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Q00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Family Medicine Physician providers in California
There are 17,133 family medicine physician records in California.
All 17,133 in California → Every provider in Placentia → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Shirley Chung, M. D.Placentia, CA 928701568682771
- Edward Drake, D.O.Placentia, CA 928701629132592
- Helen Ha, DOPlacentia, CA 928701316574783
- Lina Kim, DOPlacentia, CA 928701114457025
- Steven Le, M.D.Placentia, CA 928701083932198
- Rasha Soliman, M. D.Placentia, CA 928701831319045
- Rachel Wang, PA-CPlacentia, CA 928701235645888
- Lawrence Brownlee, M.D.Orange, CA 928691073658522
Common questions
What is Warren Woo, M.D.'s NPI number?
Warren Woo, M.D.'s National Provider Identifier (NPI) is 1447340336, issued on Oct 13, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Warren Woo, M.D. located?
The NPPES record lists a practice address at 1275 N Rose Dr, Placentia, CA, 92870. Phone: (714) 961-1635. Providers update this record themselves, so call before visiting.
How can I verify Warren Woo, M.D.'s license?
NPPES lists California license number C40927, 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 Warren Woo, M.D. prescribe under Medicare Part D?
In 2024, Warren Woo, M.D. had 1,677 Medicare Part D claims for 280 beneficiaries; the average among family medicine physician prescribers was 3,544. Part D covers Medicare prescriptions only.
What is Warren Woo, M.D.'s MIPS final score?
The 2023 MIPS final score is 76.3 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.