Connecticut · Eastern Time
Stamford, CT Area Codes
Stamford is served by 2 area codes (203, 475). Here's which is original, which are overlays, and how to pick one for a new local number.
Last updated October 3, 2026 · Source: NANPA
Area codes serving Stamford
Stamford sits in Connecticut, part of the Northeast region and the Eastern Time zone. Its numbers are spread across an overlay of 2 codes that all cover the same ground: 203, 475.
The original code is 203 (in service since 1947). As the area ran low on numbers, regulators added overlay codes on top instead of splitting the city, so longtime residents kept their numbers while new lines received a newer code.
| Code | Area served | In service |
|---|---|---|
| 203 | Southwestern Connecticut including Bridgeport, New Haven, Stamford and Waterbury | January 1, 1947 |
| 475 | Southwestern Connecticut including Bridgeport, New Haven, Stamford and Waterbury | December 12, 2009 |
Nearby cities sharing these area codes
- Bridgeport
- New Haven
- Waterbury
- Norwalk
- Danbury
- Greenwich
- Hamden
- Meriden
- Milford
- Stratford
- Fairfield
- West Haven
- Shelton
- Naugatuck
How to pick an area code for a new number
When you activate a new line in Stamford, the carrier assigns whichever code has numbers available — you usually can't choose. If a specific code matters to you (for example the prestige of 203), ask the carrier whether any blocks remain, or request a number transfer. All codes here dial identically and cost the same.
Dialing in Stamford
Because Stamford is an overlay area, 10-digit dialing is mandatory: always dial the area code plus the seven-digit number, even for a neighbor. From outside the US, dial +1, then the area code and number. See 10-digit dialing and overlay area codes for the background. For every code in Connecticut, visit the Connecticut area codes page.
Quick answers
Stamford area code FAQ
What area codes does Stamford use?
Stamford, CT is served by 2 area codes: 203, 475.
Which is the original Stamford area code?
203 is the original code for Stamford, in service since 1947; the others were added later for more numbers.
What time zone is Stamford in?
Stamford is in the Eastern Time zone.
Do I need to dial the area code in Stamford?
Yes. With multiple overlapping codes, 10-digit dialing is required for every call in this area.