Area Code 605-999 located in LETCHER, SANBORN, SD, more detail is as below. Place NPA (Numbering Plan Area) : 605 NXX (Local Number Prefix) : 999 City : LETCHER County : SANBORN State : SD (South Dakota) NXX Use Type : Wireless NXX Intro Version : 1994-02-04 FIPS (Federal Information Processing Standards) : 46111 LATA (Local Access Transport Area) : 640 Rate Center : MITCHELL ZIP Code Count : 1 ZIP Code Frequency : 50 ZIP Code : 57359 Other Information NPANXX : 605999 Switch CLLI (Common Language Location Identifier) : SXFLSDTUCM0 Time Zone : Central (GMT -06:00) Observes Daylight Saving Time : Yes Company : CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD OCN (Operating Company Number) : 6569 Coverage Area Name : MITCHELL Latitude : 43.7085 Longitude : -98.0218 ‹ previous : 605-997 next › : 605-999 Telephone Number List 605-999-0000 ~ 605-999-9999