Sign Regulations in O'Fallon, MO (2026)
3 verified sign regulations for O'Fallon, Missouri, sourced directly from the municipal code and official government pages.
Verified from official government sources
Digital Billboards
O'Fallon allows digital billboards along its regulated highway corridor, but Section 410.170(B)(5) bans flashing, scrolling or animation: the display must hold static for at least ten seconds between changes and change instantly. Brightness is capped at 5,000 nits by day and 300 nits at night, with an automatic dimmer required to make the switch.
O'Fallon Digital Billboard Brightness Rules
Some RestrictionsO'Fallon Code § 410.170(B)(5)
Digital Billboards. Billboards having a digital display (digital billboards) are permitted, provided that such billboards do not flash, scroll or employ any form of animation or moving images. Digital billboards must present a static display that changes no more frequently than every ten (10) seconds. ... The digital billboard must not exceed a maximum illumination of five thousand (5,000) nits...
Window Signs
O'Fallon lets businesses put signs in their windows without a permit, but Section 410.120(A)(14) caps them at twenty percent of the window, or of a series of contiguous windows. Go over that, and City staff can order the display down or treat it as an unpermitted wall sign.
O'Fallon Window Sign 20% Coverage Cap
Light RestrictionsO'Fallon Code § 410.120(A)(14)
Window Signs And Displays. Window signs shall not cover more than twenty percent (20%) of the window or a series of contiguous windows. Merchandise, pictures or models of products that are not affixed or touching the window but are visible through the window, that are not intended to be part of the signage, are not considered signs. Any sign placed on the outside of a window, except for individ...
Freeway-Facing Signs
O'Fallon confines billboards to a narrow band along its interstates: Section 410.170(B)(1)(a) requires a non-residentially zoned site within 660 feet of the nearest edge of the Interstate 64 or Interstate 70 right-of-way, and the billboard must actually be visible from that highway. Miss either condition and the sign cannot be permitted anywhere in the City.
O'Fallon Billboards Must Sit Near I-64/I-70
Significant RestrictionsO'Fallon Code § 410.170(B)(1)(a)
No billboard sign shall be maintained, erected, or located anywhere in the City unless: (1) The proposed site for such billboard sign is in an area of the City then zoned non-residential; and, (2) The proposed site of such billboard sign is within six hundred sixty (660) feet of the nearest edge of the right-of-way of, and visible from, Interstate Highway 64 and Interstate Highway 70.
Looking for St. Charles County county-wide rules?
County ordinances apply to unincorporated areas and may supplement O'Fallon city rules.
Sign Regulations in St. Charles County →