Zoning in Franklin County, Missouri

How the zoning system is structured

Franklin County's zoning authority runs through three distinct bodies. The Planning and Zoning Department, based at the county Government Center (400 E. Locust Street, Union, Missouri), is the administrative office: it processes land divisions, lot-line adjustments, address assignments, road naming, floodplain development permits, and applications for rezoning, conditional use permits, and subdivision plats. The Planning and Zoning Commission is the appointed citizen body that reviews and makes recommendations on rezoning requests, Planned Unit Developments (PUDs), and preliminary plats, typically meeting the third Tuesday of the month (when there is business on the agenda) in the Government Center's Commission Chambers. A separate Board of Zoning Adjustment (BOZA) handles variance requests -- cases where a specific property can't meet a literal zoning requirement (a setback, for instance) and the owner needs relief without a full rezoning.

The full zoning and subdivision code is compiled as the county's "Unified Land Use Regulations," covering zoning districts and permitted uses, subdivision review standards, floodplain management, and related development topics. The county provides this electronically as a courtesy (with a caveat that individual articles may not always reflect the most current amendment), or sells a complete paper binder copy for $35 with advance notice. Because zoning ordinances are amended periodically -- as the 2026 data center episode below shows vividly -- always confirm you're looking at the current version, or call the Planning & Zoning Department directly (636-583-6369), rather than relying on an older PDF you find independently.

Rezoning and PUDs are real, active processes here

Unlike a non-zoned Missouri county where "zoning" is a non-issue, Franklin County's rezoning and PUD process regularly produces real outcomes that shape what a specific parcel can become. Recent commission actions on the public record include a rezoning and Planned Unit Development Final Development Plan for a 198-lot subdivision near Highway 100 and Hogan Road in Boles Township, and a rezoning request for a 13.44-acre tract at 3442 Highway A in Union Township from the 'Y' zoning district to the 'R' district. Separately, McBride Homes has been developing Rock Ridge, a 156-lot subdivision east of Rock Road near the Highway 47/50 interchange in Union -- concrete evidence of the pace and scale of residential platting activity the county's zoning and subdivision-review process is currently handling.

If your interest in a Franklin County parcel includes eventually subdividing it, seeking a PUD for a multi-unit development, or getting a specific use approved that isn't permitted outright in its current district, budget real time for this process: it involves a Planning and Zoning Commission hearing (monthly cycle), likely public notice to neighboring property owners, and potentially a County Commission vote on the final rezoning ordinance. This is a meaningfully longer and more procedurally involved path than in a non-zoned county where no such review exists at all.

The 2026 data center zoning fight, in more detail

The clearest live demonstration of how Franklin County's zoning power actually functions is the 2026 fight over data center regulations. Data centers -- large, high-power-demand computing facilities -- became a live zoning issue in the county as developers eyed sites along the I-44 corridor near St. Louis-area electrical infrastructure. According to converging news coverage (Spectrum News, St. Louis Magazine, the Missourian, and the Sierra Club), proposed zoning-code amendments to specifically address data centers were tabled by the Planning and Zoning Commission in January 2026 for further review. Commissioners were reportedly told a one-year moratorium couldn't be adopted without triggering a fresh public-hearing requirement, so the county instead voted to table the matter for six months. The Planning and Zoning Commission then took up revised data-center proposals at a March 17, 2026 meeting relocated to Union High School to accommodate expected public turnout -- itself a signal of how much public interest the issue drew.

Proposed provisions that generated the most community pushback reportedly included allowing data centers to be sited as close as 150 feet from residential property lines, and eliminating the requirement for public hearings on future data center project approvals -- both read by opponents as reducing, rather than increasing, public input on a use with real neighborhood impact (noise, visual, and electrical-infrastructure concerns are common objections to data centers nationally). After a public hearing reported to have run roughly 13 hours, the Franklin County Commission ultimately moved to a longer moratorium on new data center applications -- reported by local radio coverage as a three-year pause enacted around early September 2026 -- with commissioners stating a need for further research and a developed policy before considering new applications.

For a land buyer, the specific outcome (a moratorium, its exact length, and whatever permanent ordinance eventually replaces it) is less important than the pattern it demonstrates: Franklin County's Planning and Zoning Commission and County Commission are actively willing to rewrite use-specific rules under public pressure, on a timeline of months rather than years. If a parcel you're evaluating sits anywhere near a plausible large-scale development site (existing substations, high-capacity transmission lines, or large flat tracts already being discussed for a specific project), don't assume today's zoning designation or a pending moratorium will still describe the situation in twelve months -- call the Planning and Zoning Department for the current status before you rely on it.

What to check before buying with a specific zoning outcome in mind

1. Confirm a specific parcel's current zoning district directly with the Planning and Zoning Department (636-583-6369) -- don't rely on a listing description or an older map, especially near an incorporated city's limits or a recently rezoned area.
2. If your plan depends on a use that isn't clearly permitted outright in the current district, ask specifically whether it requires a conditional use permit, a variance through the Board of Zoning Adjustment, or a full rezoning -- these are different processes with different timelines and hearing requirements.
3. If subdivision or a PUD is part of your plan, review the current Unified Land Use Regulations' subdivision-review article and budget for the Planning and Zoning Commission's monthly hearing cycle, plus any required public notice period.
4. If the parcel is anywhere near existing high-voltage transmission infrastructure or a large flat tract that could interest a data-center or similar large-scale developer, ask the Planning and Zoning Department directly about the current status of data-center zoning rules and any moratorium in effect.
5. Because Franklin County's zoning is real and actively enforced, get written confirmation of a parcel's zoning district and any pending nearby rezoning cases before finalizing a purchase price, rather than assuming rural-looking land here carries no zoning constraints.