Sent TeamMar 8, 2026 / area code / Article
Area code 203: Connecticut location, cities, dialing guide (2025)
Where is area code 203? Complete guide to Connecticut's 203/475 area codes: cities, dialing instructions, getting a number, and overlay details.
Frequently Asked Questions
What area code is Bridgeport Connecticut?
What area code is New Haven CT?
Is Stamford CT in area code 203?
What area code is Norwalk CT in?
What is the area code for Waterbury CT?
Why does area code 203 have mandatory 10-digit dialing?
What counties in Connecticut use area code 203?
When was area code 203 created?
When was area code 475 added to the 203 region?
Who regulates area code 203 in Connecticut?
What major cell phone carriers serve the 203 area code?
What is the North American Numbering Plan (NANP)?
When did Southern New England Telephone stop serving area code 203?
How many phone numbers are available in area code 203 with the overlay?
How many phone numbers are available in area code 203?
How to dial a 203 number from another area code?
Why does area code 203 have an overlay?
What is the area code for New Haven CT?
When should I use 10-digit dialing for 203?
What counties are covered by area code 203?
What is area code 203's history and establishment date?
What telecom companies service area code 203?
What is the NPA for southwestern Connecticut?
Can I still get a landline with area code 203?
What does the 475 area code overlay in Connecticut mean?