James Byron Darnton, M.D.
Internal Medicine Physician · Seattle, WA
James Byron Darnton, M.D. is an internal medicine physician with a practice address in Seattle, Washington, and NPI 1396087227, issued on Mar 18, 2013. Check the license (Washington ML 60358691, as entered in NPPES) on the Washington Medical Commission; the Medicare figures below come from public CMS files.
- Name
- James Byron Darnton
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- ML 60358691 WA
Self-reported in NPPES; status is on the state search - Practice location
- 325 9TH Ave, Seattle, WA 98104
- Phone
- (206) 744-9700
- Enumerated
- Mar 18, 2013
- Record last updated
- Jul 19, 2013 (not updated in 13 years: call before relying on the address or phone)
- Fax
- (206) 744-8516
- Medicare enrollment
- Enrolled (PECOS I20160407001337); accepts Medicare assignment
- Medical or professional school
- Perelman School Of Med At The University Of Pennsylvania, 2013
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 3,079 in Washington → Look up another NPI →
Also registered at 325 9TH Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Noor Aaf, PA-CMedical Physician Assistant1558394171
- Sheida Aalami, M.D.Internal Medicine Physician1730573296
- Collette AbbottHospitalist Physician1306208293
- Akrm Abdalrahman, MD, MSCritical Care Medicine (Anesthesiology) Physician1801374905
- Martin Abdo, COUNSELORCounselor1821202904
- Nauzley Abedini, M.D.Hospice and Palliative Medicine (Internal Medicine) Physician1043637408
Verify James Byron Darnton in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWashington Medical Commission
Search for license ML 60358691Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
22% fewer Medicare Part D claims than the average internal medicine physician in 2024
2,485 Medicare Part D claims for 108 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 15% of claims. 204 claims were for opioids.
Most prescribed
- Atorvastatin Calcium115 claims
- Amlodipine Besylate88 claims
- Albuterol Sulfate Hfa81 claims
- Oxycodone Hcl79 claims
- Gabapentin78 claims
- Lisinopril62 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 MIPS final score for 2023 (Medicare payment program): 93.1 of 100
The Merit-based Incentive Payment System score is reported for this clinician. 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; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- The Association OF University PhysiciansSeattle, WA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
James Byron Darnton among 3,079 internal medicine physician records in Washington
James Byron Darnton, M.D. is one of 3,079 internal medicine physician records with a practice address in Washington. 75% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2013, is newer than 71% of them.
- NPI issued2013 · 71% of these records are older, 27% newer
- In a Medicare fileYes · 75% of these records are
- In the CMS Doctors and Clinicians fileYes · 60% of these records are
- Graduated2013 · median 2006 among the 1,852 with a school on file
- Record last updated2013 · 63% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Washington practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
821 internal medicine physician records list a practice address in Seattle
They are 821 of the 41,956 NPPES records with a practice address in Seattle, and 3,079 internal medicine physician records in Washington.
All 3,079 in Washington → Every provider in Seattle → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Paul Abdallah, MDSeattle, WA 981041639166119
- James Bushyhead, MDSeattle, WA 981041366439846
- Michael Cairns, MDSeattle, WA 981041184611659
- Linda Chow, MDSeattle, WA 981041962498014
- Alex Efird, MDSeattle, WA 981041669469144
- Seth Franklin, MDSeattle, WA 981041588650253
- Margo Kober, MDSeattle, WA 981041083601561
- Eva KojnokSeattle, WA 981041720075294
Common questions
What is James Byron Darnton, M.D.'s NPI number?
James Byron Darnton, M.D.'s National Provider Identifier (NPI) is 1396087227, issued on Mar 18, 2013. An NPI identifies a provider in billing; it is not a license.
Where is James Byron Darnton, M.D. located?
The NPPES record lists a practice address at 325 9TH Ave, Seattle, WA, 98104. Phone: (206) 744-9700. Providers update this record themselves, so call before visiting.
How can I verify James Byron Darnton, M.D.'s license?
NPPES lists Washington license number ML 60358691, as entered by the provider. Search the Washington Medical Commission at https://wahelms.my.site.com/s/license-search. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does James Byron Darnton, M.D. prescribe under Medicare Part D?
In 2024, James Byron Darnton, M.D. had 2,485 Medicare Part D claims for 108 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is James Byron Darnton, M.D.'s MIPS final score?
The 2023 MIPS final score is 93.1 of 100. 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.