Benjamin Siemanowski, M.D.
Gastroenterology Physician · Bellingham, WA
Benjamin Siemanowski, M.D. is a gastroenterology physician with a practice address in Bellingham, Washington, and NPI 1548301120, issued on Feb 8, 2007. Check the license (Washington MD00047499, as entered in NPPES) on the Washington Medical Commission; the Medicare figures below come from public CMS files.
- Name
- Benjamin Siemanowski
- Credential
- M.D.
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License number
- MD00047499 WA
Self-reported in NPPES; status is on the state search - Practice location
- 3111 Woburn St Ste 201, Bellingham, WA 98226
- Phone
- (360) 734-1420
- Enumerated
- Feb 8, 2007
- Record last updated
- May 24, 2023
- Fax
- (360) 733-1659
- Medicaid ID
- 1548301120 WA
- Medicare enrollment
- Enrolled (PECOS I20070525000302); accepts Medicare assignment
- Medical or professional school
- Jefferson Medical College Of Thomas Jefferson University, 2000
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 533 in Washington → Look up another NPI →
Also registered at 3111 Woburn St Ste 201
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Jash Bansal, M.D.Gastroenterology Physician1225484207
- Jody Bauer, ARNPFamily Nurse Practitioner1003904061
- Megan Britson, PAPhysician Assistant1194149617
- Alan Chang, M.D.Gastroenterology Physician1255398285
- Alison Freeman, MDGastroenterology Physician1235454091
- Donald Gullickson, M.D.Gastroenterology Physician1275775058
Verify Benjamin Siemanowski in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWashington Medical Commission
Search for license MD00047499Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
39% more Medicare Part D claims than the average gastroenterology physician in 2024
1,125 Medicare Part D claims for 550 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D. Brand-name drugs were 22% of claims.
Most prescribed
- Sod Sulf-Potass Sulf-Mag Sulf314 claims
- Omeprazole279 claims
- Pantoprazole Sodium54 claims
- Mesalamine53 claims
- Peg 3350-Electrolyte52 claims
- Azathioprine32 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): 87.2 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).
Bills Medicare through one group practice
- Northwest Gastroenterology Professional LLCBellingham, WA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Benjamin Siemanowski among 533 gastroenterology physician records in Washington
Benjamin Siemanowski, M.D. is one of 533 gastroenterology physician records with a practice address in Washington. 76% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2007, is newer than 52% of them.
- NPI issued2007 · 52% of these records are older, 36% newer
- In a Medicare fileYes · 76% of these records are
- In the CMS Doctors and Clinicians fileYes · 70% of these records are
- Graduated2000 · median 2003 among the 373 with a school on file
- Record last updated2023 · 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 207RG0100X and a Washington practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in Washington
There are 533 gastroenterology physician records in Washington.
All 533 in Washington → Every provider in Bellingham → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Jash Bansal, M.D.Bellingham, WA 982261225484207
- Alan Chang, M.D.Bellingham, WA 982261255398285
- Alison Freeman, MDBellingham, WA 982261235454091
- Joseph Gabriel Gabriel, M.D.Bellingham, WA 982261417339037
- Donald Gullickson, M.D.Bellingham, WA 982261275775058
- Wen-Huan Ho, MDBellingham, WA 982261548469281
- Natasha Muckova, M.D.Bellingham, WA 982261790874048
- Kristina Ross, MDBellingham, WA 982261568738458
Common questions
What is Benjamin Siemanowski, M.D.'s NPI number?
Benjamin Siemanowski, M.D.'s National Provider Identifier (NPI) is 1548301120, issued on Feb 8, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Benjamin Siemanowski, M.D. located?
The NPPES record lists a practice address at 3111 Woburn St Ste 201, Bellingham, WA, 98226. Phone: (360) 734-1420. Providers update this record themselves, so call before visiting.
How can I verify Benjamin Siemanowski, M.D.'s license?
NPPES lists Washington license number MD00047499, 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 Benjamin Siemanowski, M.D. prescribe under Medicare Part D?
In 2024, Benjamin Siemanowski, M.D. had 1,125 Medicare Part D claims for 550 beneficiaries; the average among gastroenterology physician prescribers was 811. Part D covers Medicare prescriptions only.
What is Benjamin Siemanowski, M.D.'s MIPS final score?
The 2023 MIPS final score is 87.2 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.