A person who constructs or builds real estate without having a definite purchaser or tenant under contract at the time construction begins. The builder begins the construction with the opinion that due to the location of the property, quality of construction, and/or general business conditions a purchaser or tenant will step forward prior to completion of the project. Speculative building is particularly common in the housing industry, especially during times of low interest rates and increases in the demand for housing. In contrast, a contract builder has entered into a contract with someone to build or construct a structure for them.

A contractor who buys a piece of land and builds a house or other building for sale with his own or borrowed money without securing a buyer beforehand.