Doctor profile · Federal record

Dr. Diane Sun, MD

Internal Medicine Physician (CMS: Internal Medicine) · Boston, MA

  • NPI 1245721018
  • Accepts Medicare
  • 8 yrs in practice
  • Female
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
800 Washington St
Boston, MA 021111552
(617) 636-5000
Mailing address
110 Newbury St Apt 4R
Boston, MA 021162945

Credentials & registration

NPPES · NUCC
NPI registered
May 2018 — 8 yrs on file
Year of graduation
2018 — 8 yrs since
Specialty taxonomy
207R00000X — NUCC code
State license (1)
Massachusetts #276319

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1245721018. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
307
Distinct HCPCS
6
Medicare allowed
$32,178
HCPCS Description Services Patients Avg allowed
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 138 58 $83
99233 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 67 33 $126
99238 Hospital discharge day management, 30 minutes or less 54 53 $87
99223 Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 23 22 $185
99239 Hospital discharge day management, more than 30 minutes 13 13 $123
99222 Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 12 12 $139

In context: peer comparison

Among 547 peers in this city , average services per provider: 81. This provider delivers 3.8× the peer median.

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Diane Sun's medical specialty?
Dr. Diane Sun practices Internal Medicine Physician in Boston, MA.
Where does Dr. Diane Sun practice?
Dr. Diane Sun practices at 800 Washington St, Boston, MA 021111552. Office phone: 6176365000.
What is Dr. Diane Sun's NPI?
Dr. Diane Sun's National Provider Identifier (NPI) is 1245721018, issued by NPPES.
Does Dr. Diane Sun accept Medicare assignment?
Yes. Dr. Diane Sun accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Diane Sun commonly perform?
Top Medicare-reported procedures in 2023: Subsequent hospital care with moderate levelof medical decision making (HCPCS 99232); Subsequent hospital care with moderate levelof medical decision making (HCPCS 99233); Hospital discharge day management (HCPCS 99238). Source: CMS Medicare Physician & Other Practitioners file.