Area Code Lookup
What Area Code Is Gaithersburg?
3 area codes serve Gaithersburg · Maryland
Gaithersburg is served by area codes 227, 240, 301. It is located in Maryland.
Area Codes Serving Gaithersburg
Frequently Asked Questions
What area code is Gaithersburg?
Gaithersburg is served by area codes 227, 240, 301. It is located in Maryland.
Why does Gaithersburg have multiple area codes?
As demand for phone numbers increased, NANPA added area codes through splits (dividing the region) or overlays (layering a new code over the same geography). Gaithersburg now has 3 area codes — 227 and 240 and 301 — covering the same or overlapping areas.
How do I call Gaithersburg from outside the US?
To call Gaithersburg from abroad, dial +1 followed by the area code and 7-digit local number (e.g. +1-227-XXX-XXXX). The +1 is the country code for all NANPA countries.