Area Code and Exchange (509) 857 in Washington
Exchange Code 857 for Area Code 509 covers the city of Thorp, Kittitas County in the State of Washington. It is centered at N 47º 4' 4.45", W 120º 40' 16.27". This Exchange Code was introduced on 4 February 1994 and is designated as being used for Landline telephones.
This Exchange covers telephone numbers ranging from (509) 857-0000 to (509) 857-9999.
Technical Information for Exchange (509) 857
NXX/Exchange Code: 857
Rate Center: ELLENSBURG
Time Zone: PST
Exchange Status: Active
NXX Intro Date: 4 February 1994
CBSA Code: 21260
Number Pooling: Yes
Number Pooling in Exchange (509) 857
The initial set up of an Exchange was to have all 10,000 numbers (0000 - 9999) for a particular Rate Center allocated to the same local exhange carrier. With the advent of multiple carriers, allocating each one of them their own Exchange Code would be inefficient and soon use up the available number pools for a particular area. To counter this, some exchanges are split into blocks of 1,000 numbers, which can each be allocated to individual carriers. This cuts down on wasted numbers that aren't allocated as each carrier has a smaller pool available.Number Pooling is activated in Exchange 509-857 and the following thousand blocks are currently assigned to carriers.