Mark Lo, M.D.
NPI 1649488123 · Pediatric Emergency Medicine (Pediatrics) Physician · Seattle, WA
Enrolled with Medicare as Practitioner - Pediatric Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Lo, M.D. is a Pediatric Emergency Medicine (Pediatrics) Physician provider in Seattle, WA (NPI 1649488123).
Provider details
- NPI number
- 1649488123
- Entity type
- Individual
- Primary specialty
- Pediatric Emergency Medicine (Pediatrics) PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- A99569 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
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
- 2007-05-18
- Last updated
- 2011-05-31
Frequently asked questions
- What is Mark Lo's NPI number?
- Mark Lo's National Provider Identifier (NPI) is 1649488123, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Lo's specialty?
- Mark Lo is listed in the NPPES registry with a primary specialty of Pediatric Emergency Medicine (Pediatrics) Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Lo located?
- Mark Lo's practice location on file with NPPES is 4800 Sand Point Way Ne, M/S B5520, Seattle, WA 98105.
- What is Mark Lo's phone number?
- The practice phone number listed in the NPPES registry for Mark Lo is (206) 987-2599.
- Does Mark Lo accept Medicare?
- Mark Lo is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Lo's NPI active?
- Yes — Mark Lo's NPI (1649488123) is active in the NPPES registry as of the last update on 2011-05-31.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.