Mariann Williams, NP
Nurse Practitioner · Tonasket, WA
Mariann Williams, NP is a nurse practitioner with a practice address in Tonasket, Washington, and NPI 1922166776, issued on Dec 5, 2006. Check the license (Washington AP30003589, as entered in NPPES) with the Washington board that licenses this profession; the Medicare figures below come from public CMS files.
- Name
- Mariann Williams
- Credential
- NP
- Primary taxonomy
- Nurse Practitioner 363L00000X
- License numbers
- AP30003589 WA
RN00056504 WA
Self-reported in NPPES; status is on the state search - Practice location
- 118 S Whitcomb Ave, Tonasket, WA 98855
- Phone
- (509) 486-3191
- Enumerated
- Dec 5, 2006
- Record last updated
- Dec 4, 2025
- Fax
- (509) 223-1743
- Medicaid ID
- 1922166776 WA
- Medicare enrollment
- Enrolled (PECOS I20040630000032); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest nurse practitioner records → All 2,308 in Washington → Look up another NPI →
Also registered at 118 S Whitcomb Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Gretchen Aguilar, ARNP, FNP-CNurse Practitioner1578391249
- Ryan HunterFamily Medicine Physician1699272120
- James Jex, M.D.General Practice Physician1366496697
- Hesam Joshaghani, MDFamily Medicine Physician1689306177
- Darra Large, RNRegistered Nurse1497671226
- George LupasFamily Medicine Physician1043607138
Verify Mariann Williams in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich Washington board licenses this profession
Search for license AP30003589Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
44% fewer Medicare Part D claims than the average nurse practitioner in 2024
617 Medicare Part D claims for 143 beneficiaries, against an average of 1,109 among the 54,319 providers of this specialty who prescribed in Part D. 42 claims were for opioids.
Most prescribed
- Levothyroxine Sodium28 claims
- Omeprazole24 claims
- Losartan Potassium20 claims
- Eliquis19 claims
- Amlodipine Besylate17 claims
- Atorvastatin Calcium17 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.
Bills Medicare through one group practice
- Okanogan County Public Hospital Dist NO 4Tonasket, WA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Mariann Williams among 2,308 nurse practitioner records in Washington
Mariann Williams, NP is one of 2,308 nurse practitioner records with a practice address in Washington. 72% 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 3% of them.
- NPI issued2006 · 3% of these records are older, 78% newer
- In a Medicare fileYes · 72% of these records are
- In the CMS Doctors and Clinicians fileYes · 56% of these records are
- Graduated1994 · median 2018 among the 1,301 with a school on file
- Record last updated2025 · 47% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 363L00000X and a Washington practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
5 nurse practitioner records list a practice address in Tonasket
They are 5 of the 83 NPPES records with a practice address in Tonasket, and 2,308 nurse practitioner records in Washington.
All 2,308 in Washington → Every provider in Tonasket → Nurse Practitioner nationwide →
The 8 nurse practitioner records with the nearest ZIP codes
- Gretchen Aguilar, ARNP, FNP-CTonasket, WA 988551578391249
- Priscilla Degraff, N.P.Tonasket, WA 988551639157811
- Wanda Garrett Antuna, ARNPTonasket, WA 988551245477629
- Toni Waller, ARNPTonasket, WA 988551144867649
- Phoebe Hershenow, NPWinthrop, WA 988621306800206
- Mark Sherberg, APRNQuincy, WA 988481770023277
- Brian Bonewell, CNPOmak, WA 988411609419183
- Kevan Coffey, ARNPOmak, WA 988411174879126
Common questions
What is Mariann Williams, NP's NPI number?
Mariann Williams, NP's National Provider Identifier (NPI) is 1922166776, issued on Dec 5, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Mariann Williams, NP located?
The NPPES record lists a practice address at 118 S Whitcomb Ave, Tonasket, WA, 98855. Phone: (509) 486-3191. Providers update this record themselves, so call before visiting.
How can I verify Mariann Williams, NP's license?
NPPES lists Washington license number AP30003589, as entered by the provider. Search the Washington board that licenses this profession; the NPPES record confirms identity only.
How much does Mariann Williams, NP prescribe under Medicare Part D?
In 2024, Mariann Williams, NP had 617 Medicare Part D claims for 143 beneficiaries; the average among nurse practitioner prescribers was 1,109. Part D covers Medicare prescriptions only.
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.