Reference Data Rate Center Directory MARK, IA Rate Center MARK — IA Data last updated: March 10, 2026 LATA 632 State IA Area Codes 1 Exchanges (NXX) 1 Carriers 1 Coordinates 40.66063858496548, -92.51298644179455 Area Codes 641 Top Carriers Carrier OCN NXX Count CITIZENS MUTUAL TELEPHONE COOPERATIVE 1129 1
