2026 NPPES data Family Medicine Physician NPI 1619409273 MD
Verify on CMS →

JOSIAH BELZER, MD

Family Medicine Physician in KENT, Washington. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
1K
Medicare Part D claims · 190 beneficiaries · Family Medicine Physician avg: 3K
Generic prescribing
90%
generic claims · 10% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$16.8
1 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

JOSIAH BELZER, MD filed 1,032 Medicare Part D claims in 2023 as a Family Medicine Physician in KENT, Washington, prescribing 90% generic.

1K
Part D claims, 2023
90%
generic prescribing
$16.8
industry payments (Sunshine Act)

Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) — no proprietary rating or editorial opinion is applied.

JOSIAH BELZER, MD's Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

1,032 Top 24% higher than 76% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). This entry sits in this band. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source CMS Medicare Part D Prescriber Public Use File · 2023

Board-eligible specialty (heuristic — not verified)

JOSIAH BELZER, MD practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about JOSIAH BELZER, MD?

Quality data not reported

NPI registry status

Active

Issued 03/31/2017

NPI 1619409273

Primary specialty

Family Medicine Physician

High-volume

147,640 US NPIs in this specialty

Medicare Part D claims

1,032 70% vs specialty avg

2023 prescription claims

Specialty avg: 3,418

Specialty distribution in Washington

How Family Medicine Physician compares to other specialties among Washington providers

Washington providers

Family Medicine Physician share within Washington

1. Family Medicine Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Family Medicine Physician share within Washington

Specialty board-certification context

Estimated specialty board-certified rate — Family Medicine Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Family Medicine Physician ABMS/AOA estimate

Est. board-certified rate (Family Medicine Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Family Medicine Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

JOSIAH BELZER, MD appears in the CMS NPPES registry as a Family Medicine Physician provider holding MD credentials at 26004 104TH AVE SE STE 101, KENT, WA, 98030, with a listed phone of (425) 251-4040. NPI 1619409273 was issued on 03/31/2017. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what BELZER most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 1,032 prescription claims written by this provider, covering 190 Medicare beneficiaries and totaling roughly $54K in drug spend, split 10% brand-name and 90% generic by claim count, with an opioid prescribing rate of 3.3%. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Family Medicine Physician is a high-volume specialty nationwide, with 147,640 enrolled providers across 56 states and an average of 3,418 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

26004 104TH AVE SE STE 101
KENT, WA 98030

Provider Details

NPI 1619409273
Specialty Family Medicine Physician
Credentials MD
Gender Male
NPI Issued 03/31/2017

Industry payments received (2024) — CMS Open Payments transparency data

The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for JOSIAH BELZER, MD. Source: openpaymentsdata.cms.gov.

Total received

$17

Largest payer

Novo Nordisk Inc

Most common payment type

Food and Beverage

Industry payments are not necessarily indicators of bias — they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.

License & disciplinary context — Washington WMC 2023 annual report

Aggregate state board data only — NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~34K Washington medical licensees in 2023 — they are NOT specific to JOSIAH BELZER, MD. To verify JOSIAH BELZER, MD's current license status, search the WMC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

88
Total board actions, Washington 2023
Across 85 cases
2.59
Actions per 1,000 licensees
Washington statewide rate
probation
Most common action type
31 cases

WMC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the Washington disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Brand vs generic prescribing mix · Typical

JOSIAH BELZER, MD — brand share 10.0%
Specialty average (est.)

10% brand-name claims vs 90% generic, on 1,032 2023 Medicare Part D claims.

The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

1,032
Total Claims
$54K
Total Drug Cost
190
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
2,433
Total Day Supply
71,569
Brand vs Generic
10% brand / 90% generic
Brand Drug Cost
$32K
Generic Drug Cost
$22K
Opioid Claims
34 (3.3% rate)

Patient Demographics

Average Patient Age
74.7 years
Avg HCC Risk Score
1.21
Gender Split
51% female / 49% male
Age Distribution
<65: 11, 65-74: 87, 75-84: 69, 85+: 23

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What JOSIAH BELZER, MD prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Atorvastatin Calcium
76
Lisinopril
56
Losartan Potassium
44
Amlodipine Besylate
39
Levothyroxine Sodium
39
Simvastatin
37
Hydrochlorothiazide
33
Pantoprazole Sodium
31
Metformin Hcl Er
Metformin Hcl
26
Omeprazole
26

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Family Medicine Physician Overview

How JOSIAH BELZER, MD fits within the Family Medicine Physician landscape nationally.

147,640
Family Medicine Physician Providers in US
56
States with Family Medicine Physician
3,418
Avg Claims per Provider

JOSIAH BELZER, MD's 1,032 claims are below the specialty average of 3,418.

Nearby Family Medicine Physician Providers in Washington

Other clinicians with the same primary specialty enrolled in Washington, drawn from the same CMS NPPES roster as BELZER.

Compare Family Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is JOSIAH BELZER, MD's specialty?
JOSIAH BELZER, MD specializes in Family Medicine Physician and practices in KENT, Washington. Credentials: MD.
How much does JOSIAH BELZER, MD prescribe under Medicare Part D?
In 2023, JOSIAH BELZER, MD wrote 1,032 Medicare Part D claims totaling $54K in drug costs for 190 beneficiaries.
Where is JOSIAH BELZER, MD located?
JOSIAH BELZER, MD is located at 26004 104TH AVE SE STE 101, KENT, WA, 98030. Phone: (425) 251-4040.
What is JOSIAH BELZER, MD's NPI number?
JOSIAH BELZER, MD's National Provider Identifier (NPI) is 1619409273, issued on 03/31/2017.
Does JOSIAH BELZER, MD prescribe more brand-name or generic drugs?
JOSIAH BELZER, MD's prescribing is 10% brand-name and 90% generic drugs by claim count, with $32K in brand drug costs.
Does JOSIAH BELZER, MD prescribe opioids?
Yes, JOSIAH BELZER, MD had 34 opioid claims in 2023 with an opioid prescribing rate of 3.3%.
How many Family Medicine Physician providers are there in the US?
There are 147,640 Family Medicine Physician providers across 56 states in the US. The average Family Medicine Physician provider writes 3,418 Medicare Part D claims per year.
What drugs does JOSIAH BELZER, MD prescribe most often?
Based on 2023 Medicare Part D data, JOSIAH BELZER, MD's most frequently prescribed drugs include Atorvastatin Calcium, Lisinopril, Losartan Potassium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does JOSIAH BELZER, MD accept Medicare?
JOSIAH BELZER, MD appears in CMS Medicare data with 1,032 Part D claims and 190 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify JOSIAH BELZER, MD's credentials?
JOSIAH BELZER, MD's NPI is 1619409273 with credentials MD. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology