Naiem Nassiri, MD
Naiem Nassiri, MD is a Vascular Surgery Physician in Darien, CT, registered under NPI 1033366745. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 330 BOSTON POST RD STE 240, Darien, CT 06820. 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 |
|---|---|---|
| 56696 | CT | Vascular Surgery Physician primary |
| 25MA09308000 | NJ | Vascular Surgery Physician |
Licences are recorded in 2 states: CT, NJ. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.
- Status
- Approved
- Provider type
- Practitioner - Vascular Surgery
- PAC ID
- 6002059276
- Enrollment ID
- I20170831001456
Medicare enrolment is recorded as approved under the provider type Practitioner - Vascular Surgery. 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.
Licensed in 2 states
This provider holds licences in 2 states: Connecticut and New Jersey. The practice address on file is in Darien, CT, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.
- Licence
- 56696
- Specialty
- Vascular Surgery Physician
Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.
What Vascular Surgery covers
A surgeon with expertise in the management of surgical disorders of the blood vessels, excluding the intracranial vessels or the heart. NUCC Health Care Provider Taxonomy, code 2086S0129X
All registered taxonomy codes
This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 2086S0129X | Vascular Surgery Physician Vascular Surgery | 56696 | CT | primary |
| 2086S0129X | Vascular Surgery Physician Vascular Surgery | 25MA09308000 | NJ | |
| 390200000X | Student in an Organized Health Care Education/Training Program | — | — |
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 | 1033366745 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Aug 25, 2008 |
| Last updated | Mar 4, 2026 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | MD |
| Practice address |
330 BOSTON POST RD STE 240 Darien, CT 06820 (203) 548-7858 Fax (203) 439-4839 |
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 | 0 | 3 | 3 | 3 | 6 | 6 | 7 | 4 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 6 | 3 | 6 | 6 | 3 | 7 | 8 |
Sum = 65 · next multiple of 10 = 70 · check digit = 5 · actual last digit = 5
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.