Willis became a community when the Great Northern Railroad decided to run a track from Houston to Chicago, and the Willis brothers donated their land in 1870 to the railroad. Willis grew in population after the trains began to travel through the town. There were hotels, dry good stores, and many other successful businesses in the 1870's and 1880's. The tobacco industry played a vital role in Willis' growth and development during that time. Other cash crops of cotton, watermelons, and tomatoes were an important part of the economy through the years. The timber industry, which still plays a role in Willis' economic growth, has been its most stable economic engine for over one hundred years.

Since the 1980's, Willis has seen its economic base change from agriculture to services, retail, and manufacturing. It is the gateway to Lake Conroe. Interstate 45 bisects the community. One mile east, U.S. Highway 75 and the Atchison, Topeka and Santa Fe rail services run parallel to Interstate 45. The George Bush Intercontinental Airport is 35 miles south of Willis. The Montgomery County Airport is 10 miles east of Willis.