UTC-5 ) ZIP codes 74074-74078 Area code(s) 405 FIPS code 40-70300 [ 2 ] GNIS feature ID 1098541 [ 3 ] Website www.Stillwater.org Stillwater ( Pawnee : Kiicawi uusi it, Ksti riwara [ 4 ] ) is a city in north-central Oklahoma at the intersection of U.S. 177 and State Highway