Treynor is located in Pottawattamie county Iowa with a geographic area of 0.6 square miles. The total population in Treynor is 942 with 47.6% male and 52.4% female. Children under age 5 represent 8.6% of the population, under age 18 equal 28.5% of the population and over age 65 is 13.1% of the population. The median household income is $77,188, per capita income is $39,254. There are a total of 369 housing units with 77.2% owner occupied. Education includes 19.8% of residents that are high school graduates and 30.4% with a bachelor's degree or higher. The average temperature in Treynor in the summer is 72 degrees, and in the winter 23 degrees.