[5] According to the United States Census Bureau, the city has a total area of 3.3 square miles (8.5 km2), all land.

Before the founding of Willis, most residents in the area lived in a settlement known as Danville, formed in the 1830s four miles west of present-day New Waverly.

[8] Several of these early Danville residents were large planters, who held numerous enslaved African Americans to work the labor-intensive tobacco crops on their plantations.

After residents of Danville refused to allow the railway through their town, Peter J. and Richard S. Willis donated a parcel of their landholdings in Montgomery County so the railroad and station stop could be built there.

[7][8][9] Upon the railroad's completion in 1872, many residents of Danville, Old Waverly, and Montgomery moved to the new town of Willis.

[8][9] Although Willis received more votes (788 to 646), it did not gain the requisite two-thirds majority, so the county seat remained officially in Montgomery.

[8] A protracted legal battle ended in 1878 when the Supreme Court of Texas ruled in favor of Montgomery.

[9] In the 1930s and 40s, the development of U.S. Route 75, along with the recovery of the lumber industry during World War II, fully revitalized the local economy.

[9][8] In the mid to late 20th century through the present, agriculture and lumber remain vital components of the Willis economy, in addition to the retail, service, and manufacturing industries.

[18] In 2008, when population estimates placed noted total residents exceeded 5000 persons, Willis adopted a Home rule city charter.

Council members are Ashley Nixon, Barney Stone, Tamara Young-Hector, Thomas Luster, and William Brown.

[21] Willis is part of District 3, Texas Senate, and represented by Republican Robert Nichols.

[22] The United States Postal Service Willis Post Office is located at 609 North Campbell Street.

Farm to Market Road 1097 connects Willis to Lake Conroe and Montgomery to the west.

[24] Sam Houston National Forest is located several miles west, north, and east of Willis.