Area code 401

Area code 401 is the sole telephone area code of Rhode Island. 401 is one of the original 86 North American area codes, which were created in 1947. Rhode Island is among the decreasing number of North American jurisdictions with only one area code.

Despite the proliferation of cell phones and pagers (especially around Providence, Pawtucket and Newport), 401 is not projected to be exhausted until 2042.

...
Wikipedia