Nelly Don was a clothing manufacturer and distributor through the 1950s. It was named after its founder, Ellen Quinlan Donnelly Reed.

The company was headquartered in Kansas City, Missouri and had additional factories in the state. During World War II they made uniforms for women in the military and factories, and underwear for men in the military.

Nelly Don manufactured 75 million dresses from 1916 to 1978 making it the largest dress manufacturer of the 20th century. They were one of the first companies to apply assembly line techniques to clothing manufacturing. It was reported that she only had to dismiss one employee in the entire history of the company.

A documentary film was made about this company titled Nelly Don: A Stitch in Time. Additional information on the film can be found at their website.