Newalla is an unincorporated community in rural eastern Oklahoma County, Oklahoma, United States. Newalla is an adaption of the Osage name for the Canadian River. The post office was opened June 22, 1904.Located just west of State Highway 270, north of Interstate 40, it is a part of the Oklahoma City Metropolitan Area.Newalla, with a current elevation of 1,148 feet, is located within the Eastern bounds of Oklahoma County and appears on the Harrah, Oklahoma U.S.