Jefferson County, MO Zoning Overlays & Bonuses: Density Bonus Law (2026)

2680(A)). Under the open space design table, Table 7-15, a developer who dedicates 20% to 50% of a site as open space can shrink the district's minimum lot size proportionally; for example, an "R-20" lot normally requiring 20,000 square feet can drop to 9,000 square feet at 50% open space dedication, and front and rear setbacks can be reduced by the same percentage, though side yard setbacks may never be reduced. 2700(C) allows an outright density bonus, an increase in the number of lots permitted, calculated from Table 7-16 for dedicating a private recreation facility, a public building, a dedicated public park, dedicated public land, or restored public or private land.

2700(D). The code's own worked example shows a 100-acre "R-20" tract normally capped at 200 lots reaching 220 lots (a 10% density increase) by combining a 5-acre park dedication with a park shelter building, each worth a 5% bonus under Table 7-16. Any land or facility dedicated for the bonus must be formally accepted by the receiving public or private entity, and its boundary recorded with the County Recorder of Deeds, before the bonus is granted.