Charles Masaki, MBCHB
NPI 1821518051 · Psychiatry Physician · Boston, MA
Enrolled with Medicare as Practitioner - Psychiatry · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Charles Masaki, MBCHB is a Psychiatry Physician provider in Boston, MA (NPI 1821518051).
Provider details
- NPI number
- 1821518051
- Entity type
- Individual
- Primary specialty
- Psychiatry PhysicianAllopathic & Osteopathic Physicians
- Credential
- MBCHB
- Sex
- Male
- Sole proprietor
- No
- License
- 272193 (MA)
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 tenure28% of score
9 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
560 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. 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.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 241 | $82 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 123 | $124 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes99223 | 60 | $181 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 59 | $136 |
| Subsequent Hospital Care With Straightforward Or Low Level of Medical Decision Making, Per Day, If Using Time, at Least 25 Minutes99231 | 25 | $51 |
| Psychiatric Diagnostic Evaluation With Medical Services90792 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2017-06-20
- Last updated
- 2021-06-30
- Certified
- 2021-06-30
Frequently asked questions
- What is Charles Masaki's NPI number?
- Charles Masaki's National Provider Identifier (NPI) is 1821518051, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Charles Masaki's specialty?
- Charles Masaki is listed in the NPPES registry with a primary specialty of Psychiatry Physician (Allopathic & Osteopathic Physicians).
- Where is Charles Masaki located?
- Charles Masaki's practice location on file with NPPES is Massachusetts General Hospital, Boston, MA 02114.
- What is Charles Masaki's phone number?
- The practice phone number listed in the NPPES registry for Charles Masaki is (617) 643-4294.
- Does Charles Masaki accept Medicare?
- Charles Masaki is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Charles Masaki's NPI active?
- Yes — Charles Masaki's NPI (1821518051) is active in the NPPES registry as of the last update on 2021-06-30.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.