Doctor profile · Federal record

Dr. Thomas O'Connor, M.D.

Internal Medicine Physician (CMS: Hematology/Oncology) · Hematology & Oncology Physician · Weymouth, MA

  • NPI 1669507141
  • Accepts Medicare
  • MIPS 83.1 / 100 · 2023
  • 25 yrs in practice
  • Licensed in 2 states
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
51 Performance Dr, Suite #110
Weymouth, MA 021893141
(781) 337-9091
Mailing address
10 Willard St
Quincy, MA 021691281

Credentials & registration

NPPES · NUCC
NPI registered
February 2007 — 19 yrs on file
Profile last updated
January 21, 2014
Year of graduation
2001 — 25 yrs since
Specialty taxonomy
207R00000X — NUCC code
State licenses (2)
District of Columbia #MD035011 · Massachusetts #231774

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1669507141. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,720
Distinct HCPCS
8
Medicare allowed
$136,391
HCPCS Description Services Patients Avg allowed
99213 Established patient office or other outpatient visit, 20-29 minutes 1,389 623 $71
99214 Established patient office or other outpatient visit, 30-39 minutes 172 129 $104
99204 New patient office or other outpatient visit, 45-59 minutes 61 61 $143
99203 New patient office or other outpatient visit, 30-44 minutes 40 40 $89
99215 Established patient office or other outpatient visit, 40-54 minutes 16 15 $154
99442 Telephone medical discussion with physician, 11-20 minutes 16 15 $71
99205 New patient office or other outpatient visit, 60-74 minutes 14 14 $194
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 10 peers in this city , average services per provider: 635. This provider delivers 2.7× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
1,044
Patients
332
Total drug cost
$1,051,591
Drug Type Claims Patients Total cost
Oxycodone Hcl Generic 136 26 $1,999
Prednisone Generic 134 37 $979
Letrozole Generic 110 36 $3,772
Abiraterone Acetate Generic 102 24 $382,157
Gabapentin Generic 69 19 $639
Lorazepam Generic 62 17 $217
Ondansetron Hcl Generic 60 45 $369
Prochlorperazine Maleate Generic 60 41 $1,051
Bicalutamide Generic 57 30 $970
Dexamethasone Generic 53 31 $640

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Thomas O'Connor's medical specialty?
Dr. Thomas O'Connor practices Internal Medicine Physician in Weymouth, MA.
Where does Dr. Thomas O'Connor practice?
Dr. Thomas O'Connor practices at 51 Performance Dr, Weymouth, MA 021893141. Office phone: 7813379091.
What is Dr. Thomas O'Connor's NPI?
Dr. Thomas O'Connor's National Provider Identifier (NPI) is 1669507141, issued by NPPES.
Does Dr. Thomas O'Connor accept Medicare assignment?
Yes. Dr. Thomas O'Connor accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Thomas O'Connor commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99213); Established patient office or other outpatient visit (HCPCS 99214); New patient office or other outpatient visit (HCPCS 99204). Source: CMS Medicare Physician & Other Practitioners file.