William Seiffert, MD
NPI 1669563284 · Internal Medicine Physician · Las Cruces, NM
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Seiffert, MD is a Internal Medicine Physician provider in Las Cruces, NM (NPI 1669563284).
Provider details
- NPI number
- 1669563284
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- MD2009-0068 (NM)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-09-27
- Last updated
- 2017-05-11
Frequently asked questions
- What is William Seiffert's NPI number?
- William Seiffert's National Provider Identifier (NPI) is 1669563284, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Seiffert's specialty?
- William Seiffert is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is William Seiffert located?
- William Seiffert's practice location on file with NPPES is 4311 E Lohman Ave, Las Cruces, NM 88011-8255.
- What is William Seiffert's phone number?
- The practice phone number listed in the NPPES registry for William Seiffert is (575) 556-6625.
- Does William Seiffert accept Medicare?
- William Seiffert is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Seiffert's NPI active?
- Yes — William Seiffert's NPI (1669563284) is active in the NPPES registry as of the last update on 2017-05-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.