Willow Brook Estates is an unincorporated community and census-designated place (CDP) in Will County, Illinois, United States.

Willow Brook Estates is known as one of the largest and oldest unincorporated towns in Illinois governed by an HOA.

[3] Despite its similar name, Willow Brook Estates is 47 miles south-east of the Village of Willowbrook in DuPage County.

[4] Willow Brook Estates is located north-east of the intersection at East Exchange Street and Stateline Road.

About 1.1% of families and 2.9% of the population were below the poverty line, including none of those under the age of eighteen or sixty-five or over.