There were 1,630 households out of which 38.3% had children under the age of 18 living with them, 56.7% were married couples living together, 10.8% had a female householder with no husband present, and 29.1% were non-families. 25.1% of all households were made up of individuals and 11.8% had someone living alone who was 65 years of age or older. The average household size was 2.57 and the average family size was 3.09.
In the city the population was spread out with 29.4% under the age of 18, 8.9% from 18 to 24, 29.3% from 25 to 44, 17.8% from 45 to 64, and 14.6% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 93.3 males. For every 100 females age 18 and over, there were 88.7 males.
The median income for a household in the city was $38,115, and the median income for a family was $46,017. Males had a median income of $29,881 versus $21,974 for females. The per capita income for the city was $16,307. About 5.7% of families and 8.6% of the population were below the poverty line, including 9.1% of those under age 18 and 18.0% of those age 65 or over.
The primary industry of the area is agriculture. The broad river valley is used to grow alfalfa, sweetcorn, maize and wheat. In the hills around the city, rocky pastures support herds of cattle. There is a processing plant for alfalfa in Wamego. The other major industry is a factory which produces attachments for earth-moving and other heavy construction equipment, wholly owned by Caterpillar, Inc.. Many of the residents of the city commute to nearby areas for employment, chiefly Manhattan, Fort Riley and Topeka.
Wamego is fast approaching the status of "Oz Capital of the World" due to the The Wizard of Oz Museum, and other local Oz-related businesses. The Oz Museum was founded in April 2004 and houses one of the largest public displays of Oz memorabilia in existence. The majority of the collection belongs to Todd Machin, who began collecting Oz memorabilia while doing a term paper on The Wonderful Wizard of Oz in college. Other oz-related businesses in Wamego are "Totoz Tacoz," the "Scizzors of Ahhhz," and the "Emerald City Market." A stretch of highway 99 that passes through Wamego is called "The Road to Oz Highway." Every October, Wamego hosts Oztoberfest.