Papillion is a city in Sarpy County in the U.S. state of Nebraska. It is the county seat of Sarpy County. Papillion is a suburb of neighboring Omaha. The town is frequently referred to as Papio. The population was 23,739 in 2009, surpassing Norfolk as the 9th largest city in Nebraska. In 2009, Papillion was named the #3 best place to live in the United States by Money Magazine, surpassing its 2007 ranking of #6.