O'Fallon, MO Property Maintenance: Vacant Lot Maintenance (2026)
Key Facts
- Height limit, vacant lots
- 8 inches, no building present
- Natural-land exemption size
- Must exceed 2 acres
- Street-frontage strip still required
- 8 inches, 20 feet back from curb
- Subdivision common ground
- Trustees/developer responsible
- Unpaid cost becomes
- First lien on property
Summary
O'Fallon's weed ordinance reaches unimproved land too: any vacant lot with no building on it must be kept under eight inches of weeds, brush or grass, the same limit that applies to built lots, and the City can cut it and bill the owner if the growth isn't removed.
...and eight (8) inches in height elsewhere on property on which no building or structure is located; provided however, that these height limitations shall not apply... The requirements of this Section shall not apply to any real property within the City limits which meets all of the following requirements: 1. Is not improved with any building or structure; 2. Is more than two (2) acres in size...
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4860992; v58 updated 2026-05-14; through 05-14-2026).
Full Breakdown
100(I) of the O'Fallon Code sets the eight-inch height limit "elsewhere on property on which no building or structure is located," a clause that applies squarely to vacant, unimproved lots rather than only to developed parcels. Owners of unimproved property are jointly and severally responsible along with any occupant, and the same twenty-foot street-frontage strip requirement applies. 100(K) lets truly natural land skip the general mowing standard only if it is unimproved, larger than two acres, and maintained as natural forested area or prairie grassland compatible with neighboring use; even then the owner must still keep an eight-inch strip along abutting streets.
Outside that carve-out, an empty lot overgrown past eight inches is treated exactly like a nuisance on a built lot: the Code Enforcement Officer measures four random spots, and if any exceed eight inches the lot is in violation. 100(G).
Violations & Fines
After four days' notice, the Code Enforcement Officer can declare the vacant lot's weeds a nuisance and order cutting within five business days. If the owner or trustee does not comply, the City removes the growth and certifies the cost to the City Clerk, who bills it as a special tax bill that becomes a first lien on the property, accruing 8% annual interest until paid; each day past the five-day deadline on a detention basin or common ground is a separate violation subject to prosecution in O'Fallon Municipal Court.
Frequently Asked Questions
Does O'Fallon's weed rule apply if my lot has no house on it?
Can I let a vacant lot grow wild as a natural area?
Who is billed if a vacant lot in a subdivision's common ground overgrows?
Sources & Official References
Other rules in O'Fallon
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