Mark J O'Connor, MD
Internal Medicine, Cardiovascular Disease in Leominster, Massachusetts
1215297270- Practice location
- 100 Hospital RD, Leominster, MA 01453-2253
- Phone
- 978-466-2052
- Fax
- 978-466-2085
- Last updated
- September 10, 2025
Mark J. O'Connor is an Internal Medicine, Cardiovascular Disease based in Leominster, MA. Mark J. O'Connor practices in Leominster, MA and has the professional credentials of MD. The NPI Number for Mark J. O'Connor is 1215297270 and holds a License No. 277574 (MA). The current practice location address for Mark J. O'Connor is 100 Hospital RD, Leominster, MA 01453-2253 and can be reached out via phone at 978-466-2052 and via fax at 978-466-2085.
Provider Profile Details
- NPI Number
- 1215297270
- Provider Name
- Mark J. O'Connor
- Credential
- MD
- Provider Entity Type
- Individual
- Gender
- Male
- Address
- 100 Hospital RD, Leominster, MA 01453-2253
- Phone Number
- 978-466-2052
- Fax Number
- 978-466-2085
- Primary Taxonomy
- Internal Medicine, Cardiovascular Disease · 207RC0000X
- Sole Proprietor
- No
- Other Names
- -- Mark J O'Connor, MD (Professional Name)
- Provider Enumeration Date
- May 24, 2012
- Last Update Date
- September 10, 2025
- Certification Date
- September 10, 2025
- NPI Status
- Active
Provider Business Practice Location Address Details
- Address
- 100 Hospital RD
Leominster, MA 01453-2253 - City
- Leominster
- State
- Massachusetts
- Zip
- 01453-2253
- Phone Number
- 978-466-2052
- Fax Number
- 978-466-2085
Provider Business Mailing Address Details
- Address
- Po Box 415348
Boston, MA 02241-5348 - City
- Boston
- State
- MA
- Zip
- 02241-5348
- Phone Number
- 800-225-8885
License Information
- License Number
- 277574
- License State
- MA
- Taxonomy
- Internal Medicine, Cardiovascular Disease · 207RC0000X · Primary
Legacy Identifiers
| Identifier | Type | State | Issuer |
|---|---|---|---|
| No legacy identifiers (Medicaid, Medicare or plan IDs) are on file for this provider. | |||
Other Internal Medicine, Cardiovascular Disease providers near Leominster, MA
View all Internal Medicine, Cardiovascular Disease providers in Leominster →- Alyssa A Cali, DOInternal Medicine, Cardiovascular Disease · NPI 1972009793
- Cardiology Associates Of N E INCInternal Medicine, Cardiovascular Disease · NPI 1194825646
- Cardiology Associates Of New EnglandInternal Medicine, Cardiovascular Disease · NPI 1699017897
- Cardiology Internists Of Leominster INCInternal Medicine, Cardiovascular Disease · NPI 1285975789
- Dr. Ellen M Gallant, MDInternal Medicine, Cardiovascular Disease · NPI 1083648786
- Dr. Nicholas M Mercadante, MDInternal Medicine, Cardiovascular Disease · NPI 1821005943
Frequently Asked Questions
What is the NPI number of Mark J O'Connor, MD?
The NPI number of Mark J O'Connor, MD is 1215297270. It was assigned on May 24, 2012 and is currently active in the NPPES registry.
What is the specialty of Mark J O'Connor, MD?
Mark J O'Connor, MD is registered under the primary taxonomy Internal Medicine, Cardiovascular Disease (code 207RC0000X), licensed in MA under license number 277574.
Where does Mark J O'Connor, MD practice?
The practice location is 100 Hospital RD, Leominster, MA 01453-2253. The office can be reached at 978-466-2052 (phone) or 978-466-2085 (fax).
What is an NPI number?
A National Provider Identifier (NPI) is a unique 10-digit identification number issued to health care providers in the United States by the Centers for Medicare and Medicaid Services (CMS). It is used in HIPAA standard transactions.
How do I verify this NPI record?
This record is sourced from the public NPPES NPI Registry maintained by CMS. You can confirm it by searching NPI 1215297270 directly on the NPPES registry website.