NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Mark Leo Timmerman, M.D.

Family Medicine Physician in Merrimack, NH · enumerated 2006.

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

National Provider Identifier

1972525574

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Registry record

Entity type Individual (Type 1)
Name Mark Leo Timmerman
Credential M.D.
Sex Male
Practice address Merrimack, NH, 03054
Fax (603) 424-8140
Enumeration date Jul 24, 2006
Last updated in NPPES Mar 7, 2023

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License NH 7663 (NH) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
140824540 Other MA BC/BS MASS BILLING #
30D0084963 Other NH CLIA NUMBER
0103422YPNH01 Other NH BC/BS INDIVIDUAL NUMBER
NH 7663 Other NH NH STATE LICENSE
B86207 Other NH HPHC BILLING NUMBER
50Y095600NH01 Other NH BC/BS NH GROUP NUMBER

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.

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Frequently asked questions

How do I verify Mark Timmerman's NPI record?
Cross-check NPI 1972525574 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1972525574 active?
Yes, as of the latest NPPES snapshot, NPI 1972525574 is active (record last updated 2023-03-07).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-03-07.