William Grzelak, D.D.S
General Practice Dentistry · Rockford, IL
William Grzelak, D.D.S is a general practice dentistry with a practice address in Rockford, Illinois, and NPI 1700952561, issued on Nov 25, 2006. Check the license with the Illinois board that licenses this profession; the federal record below is the public data PlainDoctor holds for this provider.
- Name
- William Grzelak
- Credential
- D.D.S
- Primary taxonomy
- General Practice Dentistry 1223G0001X
- Practice location
- 1410 Auburn St, Rockford, IL 61103
- Phone
- (815) 968-2008
- Enumerated
- Nov 25, 2006
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
8 nearest general practice dentistry records → All 5,276 in Illinois → Look up another NPI →
Verify William Grzelak in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich Illinois board licenses this professionCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
William Grzelak among 5,276 general practice dentistry records in Illinois
William Grzelak, D.D.S is one of 5,276 general practice dentistry records with a practice address in Illinois. 64% 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 4% of them.
- NPI issued2006 · 4% of these records are older, 68% newer
- In a Medicare fileNo · 64% of these records are
- In the CMS Doctors and Clinicians fileNo · under 1% of these records are
- Record last updated2007 · 75% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 1223G0001X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
94 general practice dentistry records list a practice address in Rockford
They are 94 of the 3,893 NPPES records with a practice address in Rockford, and 5,276 general practice dentistry records in Illinois. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 5,276 in Illinois → Every provider in Rockford → General Practice Dentistry nationwide →
The 8 general practice dentistry records with the nearest ZIP codes
- Catherine Baer-Mirza, D.D.S.Rockford, IL 611031134181779
- Daniel Johnson, DDSRockford, IL 611031225065204
- Roy McNitt, DDSRockford, IL 611031457484008
- Razvan Mirza, D.D.S.Rockford, IL 611031346202918
- Hemina Desai, D.M.D.Rockford, IL 611021306252549
- Wei Gao, DDSRockford, IL 611041003982257
- June Lallas, DDSRockford, IL 611021528041597
- Geonwoong Park, DDSRockford, IL 611021659109163
Common questions
What is William Grzelak, D.D.S's NPI number?
William Grzelak, D.D.S's National Provider Identifier (NPI) is 1700952561, issued on Nov 25, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William Grzelak, D.D.S located?
The NPPES record lists a practice address at 1410 Auburn St, Rockford, IL, 61103. Phone: (815) 968-2008. Providers update this record themselves, so call before visiting.
How can I verify William Grzelak, D.D.S's license?
Search the Illinois board that licenses this profession; the NPPES record confirms identity 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. 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.