Mount Prospect, IL Sign Regulations: Window Signs (2026)

Section 7.202G governs windows in the Village of Mount Prospect. Signs on or in windows are exempt from the permit requirements of the sign chapter as long as the total area of permanent and temporary window signs occupies no more than fifty percent of the total window surface area. Permanent lettering and temporary sale posters count together toward that single fifty percent ceiling.

The definitions in the chapter decide what gets counted. A window sign is any sign that is applied or attached to a window or is located within a building such that the sign is located to be viewed from the exterior of the building. A sign hung a few feet behind the glass therefore counts even if it never touches the pane. Window surface area is the area of a building facade which is occupied by a window, and a window is an opening in the wall of a building for admission of light containing transparent or translucent material such as glass.

Subsection H is a separate exemption for doors: signs affixed to door glass that identify the name, address, contact information or hours of an establishment.

A window display that uses changeable copy or an electronic message center must also comply with subsection 7.302H, which allows one only when incorporated into a freestanding sign and requires a static message that changes no more often than once every ten seconds. Section 7.401A requires illuminated signs within one hundred feet of a residential lot line to be turned off between eleven o'clock P.M. and seven o'clock A.M. unless the business is operating with employees on the premises.