Doctor profile · Federal record

Dr. Charles Masaki, MBCHB

Psychiatry Physician (CMS: Psychiatry) · Emergency Medicine Physician · Boston, MA

  • NPI 1821518051
  • Accepts Medicare
  • 15 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
Massachusetts General Hospital, 55 Fruit St.
Boston, MA 02114
(617) 643-4294

Credentials & registration

NPPES · NUCC
NPI registered
June 2017 — 9 yrs on file
Profile last updated
June 30, 2021
Year of graduation
2011 — 15 yrs since
Specialty taxonomy
2084P0800X — NUCC code
State licenses (2)
Massachusetts #287133 · Massachusetts #272193

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1821518051. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
500
Distinct HCPCS
7
Medicare allowed
$61,748
HCPCS Description Services Patients Avg allowed
99233 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 134 92 $126
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 133 62 $84
99223 Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 89 89 $184
99231 Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 54 26 $53
99222 Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 43 43 $138
90792 Psychiatric diagnostic evaluation with medical services 33 32 $180
99285 Emergency department visit with high level of medical decision making 14 14 $183

In context: peer comparison

Among 128 peers in Boston Psychiatry Physician, average services per provider: 69. This provider delivers 7.2× the peer median.

Frequently asked questions

Auto-generated from federal data
What is Dr. Charles Masaki's medical specialty?
Dr. Charles Masaki practices Psychiatry Physician in Boston, MA.
Where does Dr. Charles Masaki practice?
Dr. Charles Masaki practices at Massachusetts General Hospital, Boston, MA 02114. Office phone: 6176434294.
What is Dr. Charles Masaki's NPI?
Dr. Charles Masaki's National Provider Identifier (NPI) is 1821518051, issued by NPPES.
Does Dr. Charles Masaki accept Medicare assignment?
Yes. Dr. Charles Masaki accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Charles Masaki commonly perform?
Top Medicare-reported procedures in 2023: Subsequent hospital care with moderate levelof medical decision making (HCPCS 99233); Subsequent hospital care with moderate levelof medical decision making (HCPCS 99232); Initial hospital care with moderate level of medical decision making (HCPCS 99223). Source: CMS Medicare Physician & Other Practitioners file.