Home | Taxation | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | Plymouth County--treasurer 215 4th Ave Se Le Mars, IA 51031 Phone : (712) 546-7078 Cass County Of--auditor 5 W 7th St Atlantic, IA 50022 Phone : (712) 243-4570 Monona County Of--auditor 610 Iowa Ave Onawa, IA 51040 Phone : (712) 433-2191 Cass County Tax Department 5 W 7th St Atlantic, IA 50022 Phone : (712) 243-5503 Sioux County Treasurer 104 1st St Orange City, IA 51041 Phone : (712) 737-2222 Sioux County Auditor 210 Central Ave Sw Orange City, IA 51041 Phone : (712) 737-2216 Sioux County Treasurer-tax 104 1st St Se Orange City, IA 51041 Phone : (712) 737-3505 Sioux County Assessor 210 Central Ave Sw Orange City, IA 51041 Phone : (712) 737-4274 Finance Department 405 6th St Sioux City, IA 51101 Phone : (712) 279-6207 Clarke County Assessor 100 S Main St Osceola, IA 50213 Phone : (641) 342-3817