Ben Williams Sonnichsen, MD
Family Medicine Physician · Prosser, WA
Ben Williams Sonnichsen, MD is a family medicine physician with a practice address in Prosser, Washington, and NPI 1295841914, issued on Aug 23, 2006. Check the license (Washington MD00029197, as entered in NPPES) on the Washington Medical Commission; the federal record below is the public data PlainDoctor holds for this provider.
- Name
- Ben Williams Sonnichsen
- Credential
- MD
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License numbers
- MD00029197 WA
MD00017164 WA
Self-reported in NPPES; status is on the state search - Practice location
- 820 Memorial Street, Prosser, WA 99350
- Phone
- (509) 786-2010
- Enumerated
- Aug 23, 2006
- Record last updated
- Dec 5, 2011 (not updated in 15 years: call before relying on the address or phone)
- Fax
- (509) 788-1794
- Medicaid ID
- 1585801 WA
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 5,534 in Washington → Look up another NPI →
Also registered at 820 Memorial Street
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Thomas Halvorson, MDOrthopaedic Surgery Physician1578555264
Verify Ben Williams Sonnichsen in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWashington Medical Commission
Search for license MD00029197Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Ben Williams Sonnichsen among 5,534 family medicine physician records in Washington
Ben Williams Sonnichsen, MD is one of 5,534 family medicine physician records with a practice address in Washington. 73% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does not. Its NPI, issued in 2006, is newer than 8% of them.
- NPI issued2006 · 8% of these records are older, 58% newer
- In a Medicare fileNo · 73% of these records are
- In the CMS Doctors and Clinicians fileNo · 60% of these records are
- Record last updated2011 · 57% 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 Washington practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
12 family medicine physician records list a practice address in Prosser
They are 12 of the 190 NPPES records with a practice address in Prosser, and 5,534 family medicine physician records in Washington. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 5,534 in Washington → Every provider in Prosser → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Fernando Dietsch, M.D.Prosser, WA 993501962455535
- Asuquo Esuabana, MDProsser, WA 993501710096615
- Albert Fiedler II, MDProsser, WA 993501811996622
- Jonathon FoxProsser, WA 993501770226813
- Kiranmayi Korimerla, MDProsser, WA 993501174939805
- Edward LaneProsser, WA 993501013023738
- Katheryn NorrisProsser, WA 993501124089875
- Carolyn OconnorProsser, WA 993501962425322
Common questions
What is Ben Williams Sonnichsen, MD's NPI number?
Ben Williams Sonnichsen, MD's National Provider Identifier (NPI) is 1295841914, issued on Aug 23, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Ben Williams Sonnichsen, MD located?
The NPPES record lists a practice address at 820 Memorial Street, Prosser, WA, 99350. Phone: (509) 786-2010. Providers update this record themselves, so call before visiting.
How can I verify Ben Williams Sonnichsen, MD's license?
NPPES lists Washington license number MD00029197, 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.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. 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.