351

The 351 area code is an important component of Massachusetts' telecommunications system, particularly in the northeastern and central parts of the state. Introduction as an Overlay: The 351 area code was introduced as an overlay to the existing 978 area code. This implementation, which became effective on May 2, 2001, was designed to provide additional numbering resources in response to the high demand for telephone numbers in northeastern and central Massachusetts. The overlay approach allows existing 978 subscribers to retain their phone numbers, while new numbers can be assigned the 351 area code. Geographic Coverage: The 351 area code, along with the 978 area code, covers a significant portion of northeastern and central Massachusetts, including cities and towns like Lowell, Lawrence, and Fitchburg. The area represents a mix of urban, suburban, and rural landscapes, reflecting the diverse demographic and economic composition of the region. Adoption of Ten-Digit Dialing: With the introduction of the 351 overlay, ten-digit dialing (area code + phone number) became mandatory for all local calls within the 978 and 351 area codes. This requirement, aligning with the standard practice in regions with overlay area codes across the United States, was essential to manage the growing number of phone users and the consequent need for more telephone numbers in the region. These facts about the 351 area code highlight its vital role in supporting the telecommunications needs of northeastern and central Massachusetts. By providing additional numbering capacity and facilitating the transition to ten-digit dialing, the 351 area code ensures that the region's communication infrastructure can keep pace with its growth and evolving needs.