Dr. Tom Ellis Williams, MD
- Medicare services, 2019
- 14
- Medicare patients, 2024
- 12
- Part D claims, 2024
- 4,024
- Affiliated sites
- 1
- Medical group
- 1
- Practice address
- 9455 Clairemont Mesa Blvd, San Diego, CA 92123
- Practice phone
- Call (619) 528-5000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Kaiser Permanente San Diego Medical Center
San Diego, California
Find Dr. Williams' professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. Tom Ellis Williams is a family medicine physician in San Diego, California
Dr. Williams practices at Kaiser Permanente San Diego Medical Center in San Diego, California.
Dr. Williams' NPI, 1932393220, was assigned on August 30, 2007. Dr. Williams graduated from Universidad Autonoma de Guadalajara in 2003. Dr. Williams holds California license A100446.
- NPI
- 1932393220NPI Registry (opens in a new tab)
- Medicare PAC ID
- 9335239672
- NPI enumeration date
- August 30, 2007
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (619) 528-5000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 49
- Medical school graduation
- 2003
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Practice Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Tom Ellis Williams practices at Kaiser Permanente San Diego Medical Center in San Diego, California
Dr. Williams' primary practice is Kaiser Permanente San Diego Medical Center, at 9455 Clairemont Mesa Blvd, San Diego, CA 92123 in San Diego County. The practice phone is (619) 528-5000.
- Kaiser Permanente San Diego Medical Center9455 Clairemont Mesa Blvd, San Diego, CA 92123 · San Diego CountyPhone(619) 528-5000
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dr. Tom Ellis Williams is affiliated with 2 sites of care and 1 medical group
Dr. Williams' primary practice is Kaiser Permanente San Diego Medical Center in San Diego, California. The medical group on file is Southern California Permanente Medical Group. Dmand AI also links Dr. Williams to 1 more community health center, named with a free account.
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Dr. Tom Ellis Williams' practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Williams practices. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Kaiser Permanente San Diego Medical Center | Available with a free account |
| +1 more affiliated site | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Tom Ellis Williams is one of 15,680 family medicine physicians in California
Family medicine is Dr. Williams' primary specialty in the NPI Registry, under taxonomy code 207Q00000X. Dr. Williams is board certified in family medicine by the American Board of Family Medicine. Dmand AI has Dr. Williams' licenses on file in 2 states: California and New Mexico.
Specialties and state licenses
- Family medicine, CaliforniaPrimary
- New Mexico license
Clinical focus
Dmand AI lists chronic diabetes, chronic embolism thrombosis, chronic hypertension, ear eustachian tube disorders, upper respiratory infection (URI) and varicose veins among the conditions Dr. Williams treats.
Family medicine physicians near Dr. Williams
Counts of family medicine physicians with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Tom Ellis Williams billed Medicare for 14 services in 2019
CMS data shows 14 Medicare services from Dr. Williams across 1 procedure code in 2019, all of them office visits, for 12 Medicare patients. Medicare paid $391 for them. Every service was in an office.
Dr. Williams' Medicare services by type, 2017 to 2019
- 2017
- 2019
- Office and hospital visits
- 2017: 182019: 1422%
Dr. Williams compared with the California median for family medicine physicians, 2019
- Dr. Williams
- California median
- Medicare services
- 14vs 24694% below
- Medicare patients
- 12vs 11890% below
- Part D claims
- 3,499vs 8334.2 times
Medians across 15,349 family medicine physicians in California with Dmand AI profiles that report each measure.
Dr. Williams' most billed Medicare procedure codes, 2019
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
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Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Tom Ellis Williams treated 12 Medicare patients in 2024, average age 66
CMS counts 12 Medicare patients who saw Dr. Williams in 2024. Their average risk score is 1.32, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Williams' median patient age at 61, with 47% women.
Dr. Williams' patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 61
Patient panel by sex, all payers
- Women47%
- Men53%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Tom Ellis Williams wrote 4,024 Medicare Part D claims in 2024
In 2024, Dr. Williams wrote 4,024 Medicare Part D claims for 660 patients. 90% of them were for generic drugs. CMS names the drug for 3,499 of them, across 66 drugs with 11 or more claims each, at $124,237 in total drug cost. In 2023, CMS named 2,881 claims across 59 drugs.
Dr. Williams' Part D claims by kind of drug, 2024
- Generic3,621 claims90%
- Brand-name353 claims9%
- Other50 claims1%
Dr. Williams' most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Drug classes CMS tracks in Dr. Williams' Part D claims, 2024
- Opioids4%151 of 4,024 claims
- Antibiotics2%73 of 4,024 claims
Share of all Part D claims for each drug class CMS reports on. Classes with no claims are left out.
Part D claims for drugs CMS names, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 2,8812024: 3,49921%
Drugs named by CMS: 66 in 2024, 59 in 2023.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
How Dr. Tom Ellis Williams takes part in Medicare
Dr. Williams accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
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Dr. Tom Ellis Williams graduated from Universidad Autonoma de Guadalajara
Dr. Williams graduated from Universidad Autonoma de Guadalajara in 2003.
- Medical school
- Board certified in family medicine
- Board certified in family medicine
Source: Dmand AI Professional Profile Data
Dr. Tom Ellis Williams accepts plans from 2 insurance carriers
Dr. Williams is in network with 2 carriers, including Kaiser Permanente and CMS Medicare. EPO plans come from the most carriers, 1. Check the plan with the practice before a visit.
- Kaiser Permanente
- CMS Medicare
Plan types Dr. Williams accepts, by number of carriers
- EPO1
- HMO1
- Medicare1
- POS1
Source: Dmand AI Insurance Network Data
Sources for Dr. Tom Ellis Williams's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation DataDmand AI Org Hierarchy Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| Insurance carriers and plan types | Dmand AI Insurance Network Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Tom Ellis Williams
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Tom Ellis Williams' NPI number?
Dr. Tom Ellis Williams' NPI number is 1932393220. It was assigned on August 30, 2007, and it is active in the NPI Registry.
What kind of doctor is Dr. Tom Ellis Williams?
Dr. Tom Ellis Williams is a family medicine physician in San Diego, California. The primary specialty in the NPI Registry is Family Medicine Physician (taxonomy code 207Q00000X).
Where does Dr. Tom Ellis Williams practice?
Dr. Williams practices at 9455 Clairemont Mesa Blvd, San Diego, CA 92123. Dr. Williams' primary practice is Kaiser Permanente San Diego Medical Center in San Diego, California. Dmand AI also links Dr. Williams to 1 community health center.
What is Dr. Tom Ellis Williams' office phone number?
The practice phone on file for Dr. Williams is (619) 528-5000.
What is Dr. Tom Ellis Williams' medical license number?
Dr. Williams holds California license A100446, one of the licenses on file in 2 states.
Which states has Dr. Tom Ellis Williams been licensed in?
Dmand AI has state licenses on file for Dr. Williams in California (2007 to 2026) and New Mexico (2004 to 2007).
What medical group is Dr. Tom Ellis Williams part of?
Dr. Williams is linked to Southern California Permanente Medical Group.
Does Dr. Tom Ellis Williams accept Medicare?
Yes. CMS data shows Dr. Williams billed Medicare for 14 services in 2019, and Dr. Williams accepts Medicare assignment.
How many Medicare patients does Dr. Tom Ellis Williams see?
CMS counts 12 Medicare patients who saw Dr. Williams in 2024, with an average age of 66.
Is Dr. Tom Ellis Williams board certified?
Yes. Dr. Williams is board certified in family medicine by the American Board of Family Medicine.
Show 5 more questionsShow fewer questions
What services does Dr. Tom Ellis Williams bill to Medicare?
In 2019, Dr. Williams' most billed Medicare services were office visit, established patient (99213).
Where did Dr. Tom Ellis Williams go to medical school?
Dr. Williams graduated from Universidad Autonoma de Guadalajara in 2003.
What drugs does Dr. Tom Ellis Williams prescribe most?
In 2024 Medicare Part D data, Dr. Williams' most prescribed drugs by claims were Atorvastatin Calcium, Lisinopril and Amlodipine Besylate.
How long has Dr. Tom Ellis Williams been practicing?
Dr. Williams graduated from medical school in 2003, 23 years ago.
What insurance does Dr. Tom Ellis Williams accept?
Dr. Williams is in network with 2 carriers, including Kaiser Permanente and CMS Medicare. EPO plans come from the most carriers, 1. Check the plan with the practice before a visit.
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