Mary Joan O'neill, M.D.
Mary Joan O'neill, M.D. is an Emergency Medicine Physician in Milford, MA, registered under NPI 1861431959. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 14 PROSPECT ST, Milford, MA 01757. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 152946 | MA | Emergency Medicine Physician primary |
| 152946 | MA | Pediatric Emergency Medicine (Pediatrics)… |
This provider holds licence 152946 issued in MA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Emergency Medicine
- PAC ID
- 4688750102
- Enrollment ID
- I20080325000201
Medicare enrolment is recorded as approved under the provider type Practitioner - Emergency Medicine. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Emergency Medicine covers
An emergency physician focuses on the immediate decision making and action necessary to prevent death or any further disability both in the pre-hospital setting by directing emergency medical technicians and in the emergency department. The emergency physician provides immediate recognition, evaluation, care, stabilization and disposition of a generally diversified population of adult and pediatric patients in response to acute illness and injury. NUCC Health Care Provider Taxonomy, code 207P00000X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207P00000X | Emergency Medicine Physician | 152946 | MA | primary |
| 2080P0204X | Pediatric Emergency Medicine (Pediatrics) Physician Pediatric Emergency Medicine | 152946 | MA |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1861431959 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jun 5, 2006 |
| Last updated | Sep 8, 2025 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
14 PROSPECT ST Milford, MA 01757 (508) 422-2810 Fax (508) 634-3276 |
| Mailing address |
300 LONGWOOD AVE Boston, MA 02115 |
| Other identifiers |
0008333
· Other 34623 · Other J18057 · Other 999541 · Other 000000021079 · Other 613214 · Other 930104656 · Other 152946 · Other 3172155 · Medicaid (MA) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 8 | 6 | 1 | 4 | 3 | 1 | 9 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 3 | 1 | 8 | 3 | 2 | 9 | 1 |
Sum = 61 · next multiple of 10 = 70 · check digit = 9 · actual last digit = 9
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.