Prefix overview
Phone numbers in prefix 603-428
This page covers the 603-428 prefix in the United States. It shows where numbers come from, which carrier is linked to the range, and how this block is structured.
If you are looking for a specific number, you can continue to its dedicated phone page. Otherwise, this page helps you understand the broader number block behind it.
PREFIX
603-428
RATE CENTER
HENNIKER
CARRIER
MERRIMACK CO. TELEPHONE CO., DBA CONTOOCOOK VALLEY
NH
Prefix range
The prefix 603-428 includes numbers from 6034280000 to 6034289999.
This range is associated with the HENNIKER rate center and was originally assigned to MERRIMACK CO. TELEPHONE CO., DBA CONTOOCOOK VALLEY.
Numbers in this prefix
20 numbers