Individual provider

David Gagnon, MD

Family Medicine Physician Deactivated record

David Gagnon, MD is a Family Medicine Physician in Portsmouth, NH, registered under NPI 1831145259.

This NPI is deactivated. The provider has retired, changed registration, or the number was retired by CMS. Details below are kept for reference — do not rely on them to arrange care.

Getting there

The practice address on file is 100 CAMPUS DR STE 12, Portsmouth, NH 03801. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

100 CAMPUS DR STE 12, Portsmouth, NH 03801 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
7236 NH Family Medicine Physician primary
12177 ME Family Medicine Physician

Licences are recorded in 2 states: NH, ME. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Family Practice
PAC ID
9830131556
Enrollment ID
I20140516000191

Medicare enrolment is recorded as approved under the provider type Practitioner - Family Practice. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

Licensed in 2 states

This provider holds licences in 2 states: Maine and New Hampshire. The practice address on file is in Portsmouth, NH, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

ME Maine
Licence
12177
Specialty
Family Medicine Physician
Verify with the ME board →
NH New Hampshire practice address
Licence
7236
Specialty
Family Medicine Physician
Verify with the NH board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Family Medicine covers

Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity. NUCC Health Care Provider Taxonomy, code 207Q00000X
Allopathic & Osteopathic Physicians Family Medicine

All registered taxonomy codes

This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
207Q00000X Family Medicine Physician 7236 NH primary
207Q00000X Family Medicine Physician 12177 ME

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1831145259 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateMay 26, 2006
Last updatedAug 18, 2021
StatusDeactivated
Sole proprietorNo
CredentialMD
Practice address 100 CAMPUS DR STE 12
Portsmouth, NH 03801
(603) 422-8208
Fax (603) 422-8218
Mailing address 311 ROUTE 108 BUSINESS OFFICE
Somersworth, NH 03878
Other identifiers 30001207 · Medicaid (NH)
239030099 · Medicaid (ME)
The last update on file is Aug 18, 2021. Providers are only required to update NPPES when their information changes, so an older date does not necessarily mean the details are wrong — but it is worth a quick call before you travel.

Number check

1831145259 passes the NPI check digit test The final digit 9 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 8 3 1 1 4 5 2 5
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 8 6 1 2 4 1 2 1

Sum = 51 · next multiple of 10 = 60 · check digit = 9 · actual last digit = 9

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1831145259?
NPI 1831145259 is the National Provider Identifier assigned to David Gagnon, MD in Portsmouth, NH. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Family Medicine Physician cover?
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
How do I contact David Gagnon, MD?
The phone number on file with NPPES is (603) 422-8208, last updated Aug 18, 2021. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does David Gagnon, MD accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1831145259 a valid number?
Yes. 1831145259 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.