Siamak Majidi, DDS
Siamak Majidi, DDS is a provider specialising in Pediatric Dentistry in Washington, DC, registered under NPI 1003041328. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
Here is what surrounds this office in Washington, based on OpenStreetMap data collected Sep 1, 2026. Parking is available about 0.40 mi away at Colonial Parking. There is EV charging 0.45 mi from the office (ChargePoint) — useful if you are driving in from out of town. The nearest transit stop is 746 ft away, served by M St NW at Wisconsin Ave NW. A pharmacy sits 0.39 mi from the entrance (CVS Pharmacy), which helps if you leave with a prescription. If you arrive early, there is a coffee shop 442 ft away.
Getting here and what is nearby
Coffee Café Con Bagel 337 ft ~2 min
1332 Wisconsin Avenue Northwest
Coffee Mèo Maison 340 ft ~2 min
1336 Wisconsin Avenue Northwest
Mo off; Tu-Th 12:00-19:00; Fr-Su 11:00-19:00
Hotel The Georgetown Inn 317 ft ~2 min
1310 Wisconsin Avenue Northwest, Washington 20007
Restaurant Georgetown Pizza & Grill 308 ft ~2 min
Restaurant 1310 Kitchen & Bar 320 ft ~2 min
1310 Wisconsin Avenue Northwest, 20007
Mo,Tu,We 07:00-14:00; Th 07:00-22:00; Fr 07:00-23:00; Sa 07:00-24:00; Su 08:00-14:30
Restaurant Masala Eatery 325 ft ~2 min
3206 O Street Northwest
Mo off; Tu-Fr 16:00-23:00; Sa-Su 12:00-23:00
Transit Wisconsin Ave NW at Dumbarton St NW 346 ft ~2 min
Coffee Compass Coffee 442 ft ~2 min
1351 Wisconsin Avenue Northwest, Washington 20007
Mo-Fr 06:00-19:00; Sa-Su 07:00-19:00
Pharmacy CVS Pharmacy 663 ft ~3 min
Transit Wisconsin Ave NW at P St NW 745 ft ~3 min
Transit M St NW at Wisconsin Ave NW 746 ft ~3 min
EV charging 758 ft ~3 min
Gas station Georgetown Exxon 0.24 mi ~5 min
1601 Wisconsin Avenue Northwest, Washington 20007
Mo-Su 06:00-23:00
Gas station Shell 0.25 mi ~5 min
1576 Wisconsin Avenue Northwest, Washington 20007
Hotel Canal Inn Hotel 0.27 mi ~6 min
Hotel Rosewood 0.27 mi ~6 min
Convenience Wisemillers Grocery & Deli 0.32 mi ~7 min
Parking SP+ 0.32 mi ~7 min
Convenience Sara's Food Market 0.35 mi ~7 min
3008 Q Street Northwest
Convenience Scheele's Market 0.36 mi ~8 min
1331 29th Street Northwest
Parking Colonial Parking 0.36 mi ~8 min
Mo-Fr 07:00-19:00
Pharmacy CVS Pharmacy 0.39 mi ~8 min
Parking Colonial Parking 0.40 mi ~8 min
Mo-Su 07:00-24:00
EV charging ChargePoint 0.45 mi ~9 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| DEN1000816 | DC | Pediatric Dentistry |
| 0401412530 | VA | Pediatric Dentistry |
| 14345 | MD | Pediatric Dentistry primary |
Licences are recorded in 3 states: DC, VA, MD. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
Licensed in 3 states
This provider holds licences in 3 states: District of Columbia, Maryland and Virginia. The practice address on file is in Washington, DC, 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
- DEN1000816
- Specialty
- Pediatric Dentistry
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 Pediatric Dentistry covers
An age-defined specialty that provides both primary and comprehensive preventive and therapeutic oral health care for infants and children through adolescence, including those with special health care needs. NUCC Health Care Provider Taxonomy, code 1223P0221X
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 | |
|---|---|---|---|---|
| 1223P0221X | Pediatric Dentistry Pediatric Dentistry | DEN1000816 | DC | |
| 1223P0221X | Pediatric Dentistry Pediatric Dentistry | 0401412530 | VA | |
| 1223P0221X | Pediatric Dentistry Pediatric Dentistry | 14345 | MD | primary |
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 | 1003041328 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | May 17, 2009 |
| Last updated | Jan 28, 2016 |
| Status | Active |
| Sole proprietor | Yes |
| Gender | Male |
| Credential | DDS |
| Practice address |
3239 N ST NW APT 12 Washington, DC 20007 (240) 418-6103 |
| Other identifiers |
023907100
· Medicaid (MD) |
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 | 0 | 3 | 0 | 4 | 1 | 3 | 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 0 | 4 | 2 | 3 | 4 |
Sum = 42 · next multiple of 10 = 50 · check digit = 8 · actual last digit = 8
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.