Reference Data Rate Center Directory CLEAR LAKE, SD Rate Center CLEAR LAKE — SD Data last updated: March 10, 2026 LATA 640 State SD Area Codes 1 Exchanges (NXX) 1 Carriers 1 Coordinates 44.75484645561481, -96.6851899684242 Area Codes 605 Top Carriers Carrier OCN NXX Count INTERSTATE TELECOM COOP, INC. - SD 1651 1
