Area code 240 will overlay 301 beginning June 1, 1997.
ALL 301 EXCHANGE PREFIXES REMAIN IN THE 301 AREA CODE.

Area code 443 will overlay 410 beginning June 1, 1997.
ALL 410 EXCHANGE PREFIXES REMAIN IN THE 410 AREA CODE.

Mandatory ten-digit local dialing in 301 and 410 begins: May 1, 1997

Test numbers: (240) 999-8378
              (443) 999-8378

Source: Bell Atlantic, LINCS
Updated: 01/05/97
Posted by: Pierre Thomson, Telecom Manager, CE Service