William Bonzelaar, M.D.032354
Family Medicine Physician in Holland, Michigan. This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 147,640 in Family Medicine Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
What the federal data shows
William Bonzelaar, M.D.032354 filed 509 Medicare Part D claims in 2023 as a Family Medicine Physician in Holland, Michigan.
- 509
- Part D claims, 2023
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.
William Bonzelaar, M.D.032354's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
509 Top 34% higher than 66% of 1,370,886 prescribers
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
William Bonzelaar, M.D.032354 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 William Bonzelaar, M.D.032354?
Quality data not reportedPrimary specialty
Medicare Part D claims
Specialty distribution in Michigan
How Family Medicine Physician compares to other specialties among Michigan providers
Largest specialties in Michigan (% of in-state providers)
Family Medicine Physician ranks #10 among Michigan's specialties (2.1% of in-state providers)
Each bar is a specialty's share of the Michigan provider total, by primary NUCC taxonomy. The highlighted bar is Family Medicine Physician; the long tail of smaller specialties is omitted for legibility.
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Family Medicine Physician. Verify directly:
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).
William Bonzelaar, M.D.032354 appears in the CMS NPPES registry as a Family Medicine Physician provider holding M.D.032354 credentials at 904 S WASHINGTON AVE, Holland, MI, 49423, with a listed phone of (616) 392-8035. NPI 1053374165 was issued on 04/10/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Bonzelaar 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 509 prescription claims written by this provider, covering 197 Medicare beneficiaries and totaling roughly $36K in drug spend. 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
Provider Details
| NPI | 1053374165 |
|---|---|
| Specialty | Family Medicine Physician |
| Credentials | M.D.032354 |
| Gender | Male |
| NPI Issued | 04/10/2006 |
Verify this provider's license
PlainDoctor pulls this profile from the CMS NPPES public registry. Confirm William Bonzelaar, M.D.032354's current license status, disciplinary history, and board certifications with the Michigan Department of Licensing and Regulatory Affairs in Michigan before relying on this page for a clinical or care decision.
How we sourced this profile
License & disciplinary context - Michigan MI-BOM 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 ~41K Michigan medical licensees in 2023 - they are NOT specific to William Bonzelaar, M.D.032354. To verify William Bonzelaar, M.D.032354's current license status, search the MI-BOM public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
MI-BOM 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 Michigan disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
Prescribing Breakdown
- 30-Day Fills
- 1,235
- Total Day Supply
- 36,772
- Generic Drug Cost
- $9K
Patient Demographics
- Average Patient Age
- 75.9 years
- Avg HCC Risk Score
- 1.10
- Gender Split
- 45% female / 55% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What William Bonzelaar, M.D.032354 prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
31 claims
- Metformin Hcl
Metformin Hcl
28 claims
- Levothyroxine Sodium
Levothyroxine Sodium
27 claims
- Lisinopril
Lisinopril
25 claims
- Metoprolol Tartrate
Metoprolol Tartrate
22 claims
- Simvastatin
Simvastatin
19 claims
- Losartan Potassium
Losartan Potassium
18 claims
- Amlodipine Besylate
Amlodipine Besylate
16 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 31 |
| Metformin Hcl | 28 |
| Levothyroxine Sodium | 27 |
| Lisinopril | 25 |
| Metoprolol Tartrate | 22 |
| Simvastatin | 19 |
| Losartan Potassium | 18 |
| Amlodipine Besylate | 16 |
| Pravastatin Sodium | 14 |
| Omeprazole | 13 |
* 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 William Bonzelaar, M.D.032354 fits within the Family Medicine Physician landscape nationally.
William Bonzelaar, M.D.032354's 509 claims are below the specialty average of 3,418.
Nearby Family Medicine Physician Providers in Michigan
Other clinicians with the same primary specialty enrolled in Michigan, drawn from the same CMS NPPES roster as Bonzelaar.
Compare Family Medicine Physician nationally: see state-by-state distribution →
Before you book an appointment
Use this federal record as your verification checklist, not as a recommendation.
- Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
- Check the active license and any disciplinary history with the Michigan medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Family Medicine Physician peer on Medicare volume and prescribing patterns. Compare providers
Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.
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Frequently Asked Questions
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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