Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Thomas James Mertz, MD

Urology Physician in Roseville, MI · enumerated 2006.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1659337137

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)

Name Thomas James Mertz

Credential MD

Sex Male

Practice address 18325 E 10 Mile Rd, Suite 200, Roseville, MI, 48066

Phone (586) 773-6300

Fax (586) 773-6266

Enumeration date Apr 25, 2006

Last updated in NPPES Nov 5, 2018

Taxonomy & licenses

208800000X Urology Physician Allopathic & Osteopathic Physicians · License 4301035307 (MI) Primary

MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

Read the full guide → Validate an NPI →

Frequently asked questions

Is this the official NPI registry?

No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

What specialty is Thomas Mertz?

Thomas Mertz is registered in NPPES with the primary taxonomy of Urology Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Other providers at this practice address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-11-05.