Jefferson County, MO Ordinances (2026)

Jefferson County's Unified Development Order fixes minimum front, side and rear yard setbacks by zoning district in unincorporated areas, measured from the street right-of-way or…

Jefferson County caps maximum structure height by zoning district in unincorporated areas under Table 5-4, ranging from 40 feet in most residential districts up to 70 feet in…

For industrially-zoned development in unincorporated Jefferson County, impervious surface (buildings, pavement) may cover up to 80% of the development site under the Industrial Design…

Jefferson County bans dumping, depositing, throwing, or leaving litter on any public or private property or in any waters in the unincorporated county, and lets a name found on the…

Jefferson County requires trash and yard-waste containers to sit at a spot on the owner's property that the hauler and resident have already agreed on, set out on the scheduled…

Jefferson County guarantees bulky rubbish pickup, discarded appliances, furniture and other oversized items too heavy for a regular truck, twice a year under Section 250.030(F), with…

Jefferson County defines yard waste as grass clippings, leaves and debris from dead, fallen or felled trees, and Section 250.020(D) requires it to be stored in containers sturdy enough…

Every residence in unincorporated Jefferson County must have its solid waste picked up at least once a week under Section 250.030(E). The only excuses for missing that weekly minimum…

Every property owner and occupant in unincorporated Jefferson County that produces solid waste must sign up with a licensed hauler, one carrying a valid County hauling permit, under…

Non-residential trash containers and dumpsters in unincorporated Jefferson County must be screened from off-property view, with individual enclosures built of masonry, decorative wall…

Jefferson County outlaws keeping native wildlife as pets: no one may own, harbor or keep a raccoon, skunk, fox, squirrel or other Missouri-indigenous wild animal. Any dangerous wild…

Jefferson County does not ban breeds; instead its Animal Control Division declares an animal 'potentially dangerous' or 'dangerous' based on documented bites, attacks or aggressive…

Jefferson County forbids letting any dog run at large in the unincorporated county, defining at large as off the owner's property and not under the physical restraint of a person…

Jefferson County requires every cat kept in the unincorporated county to carry a paid County Animal License, treats the license as a presumption of ownership, and gives only transient…

Jefferson County requires every animal over three months old to be spayed or neutered before it can be adopted from the Animal Control Center, and requires microchipping before any…

Jefferson County's Unified Development Order lists "Pet/animal grooming and/or training" as a Table 5-1 permitted use in the unincorporated county, tagged (H) for Home Occupation. Run…

Jefferson County requires a land disturbance permit before any grading, clearing or construction activity that disturbs 5,000 square feet or more of unincorporated county land…

Unincorporated Jefferson County requires a land disturbance permit for any project disturbing 5,000 square feet or more, with structural stormwater Best Management Practices mandatory…

Jefferson County requires a floodplain development permit for any construction in mapped A, AE, AO or AH flood zones on its current FIRM panels, issued by the Director under Chapter…

Jefferson County requires new and substantially improved structures in mapped flood zones to elevate the lowest floor three feet above base flood elevation, or floodproof…

Jefferson County requires a separate building permit before erecting, altering, repairing, moving or demolishing any structure covered by the Building Code. Permits run through the…

Jefferson County requires a county Electrical License before any contractor wires, installs or alters electrical service in the unincorporated area, and a building permit before work…

Jefferson County requires a county Plumbing License before any contractor installs, alters or repairs plumbing fixtures, piping or drainage connected to a water or sewage system, plus…

A day care serving more than ten children older than two and a half, for fewer than twenty-four hours a day, is classified as a Group E occupancy under Jefferson County's amendment to…

Jefferson County's Building Code requires the Code Official to inspect permitted work at each construction stage, and forbids work from continuing past an inspection point without…

Every dwelling unit in Jefferson County needs at least one side-hinged egress door at least thirty-six inches wide and eighty inches tall that opens from inside without a key, special…

Jefferson County mandates automatic fire sprinklers in new townhouses under its amendment to IRC Section R313.1, but Missouri law bars the county from mandating them in single-family…

New homes and substantially improved existing homes in Jefferson County must power carbon monoxide alarms from 120-volt AC wiring with battery backup, interconnected with the home's…

Jefferson County's Unified Development Order leaves deed restrictions, covenants and HOA agreements entirely to private parties. Section 400.070 states flatly that the County will not…

Jefferson County's UDO sets a hard deadline for developers to hand control of a subdivision's HOA to an elected owner board: 90 days after 95% of units sell with a professional…

When a Jefferson County property owners' association fails to maintain common open space, the Director can order a fix within 30 days and refer the matter to a County Council hearing…

Jefferson County requires subdividers to form a property owners' association before any lot sells, with mandatory membership for every owner. The association owns and maintains common…

Jefferson County's UDO sets a $300 annual minimum per-lot assessment for subdivision property owners' associations that maintain sewer lines, water systems, streets or similar…

Jefferson County's Traffic Code bans muffler cutouts and requires every motor vehicle on unincorporated county roads to run a muffler quiet enough to match a modern passenger car's…

Jefferson County's UDO exempts temporary construction noise and vibration from its quantitative performance standards only between 7:00 A.M. and 7:00 P.M. Outside that twelve-hour…

Jefferson County presumes music, speech, or noise disturbs the peace once it is plainly audible more than fifty feet from its source in the unincorporated area. Radios, music players…

Jefferson County bars dogs kept in the unincorporated area from howling or barking continually beyond the property line: more than 15 minutes between 10 p.m. and 8 a.m., more than 30…

Jefferson County's Unified Development Ordinance caps data center noise at 55 dBA in the daytime and 50 dBA overnight when the equipment sits near a home, school, church or farm with a…

Once Jefferson County serves a nuisance notice, the owner has a reasonable time not exceeding ten days to start fixing the violation, and ten calendar days to appeal before the order…

Jefferson County's Public Nuisance Ordinance lists sixteen specific conditions, from junk and derelict vehicles to tall grass and dead animals, that make a property a public nuisance…

A Jefferson County nuisance case starts when someone files a complaint with the Code Official, who must inspect the property before serving written notice on the owner. Owners get up…

Jefferson County's unincorporated land carries an "RA-5" Rural/Agricultural District under UDO Section 400.1470, capping density at one home per five acres to preserve farmland and…

Jefferson County's peace disturbance ordinance names "urinating or defecating in public" as one specific act that constitutes the offense in the unincorporated area. Violators face…

Jefferson County makes it unlawful to possess or control marijuana anywhere in the unincorporated county unless the possession is authorized under Missouri's controlled-substances…

Jefferson County makes it unlawful to be intoxicated on a street, in a place of amusement, hotel, restaurant, public building, or other public place anywhere in the unincorporated…

Jefferson County pedestrians may not cross between two intersections that have working traffic control signals unless they use a marked crosswalk. Outside signalized stretches, walkers…

Jefferson County makes it unlawful for anyone on roller skates, roller blades, or a skateboard to go onto any road except to cross it. While crossing, the skater has all the rights and…

Jefferson County's Public Nuisance Ordinance declares any noxious weed or tall grass, defined as vegetation twenty inches or higher, a public nuisance on real property in the…

Yard waste composting facilities that produce compost for resale run only as a conditional use in Jefferson County's RA-5 and LR-2 residential districts. UDO Section 400.3145 caps…

Trees and foliage at Jefferson County intersections and driveways must be trimmed so nothing blocks the view between 3 and 10 feet above ground within the sight triangle, and trunks…

Clearing significant trees or trees of 10-inch caliper or larger on a development site in unincorporated Jefferson County requires an approved tree conservation plan first. The…

Jefferson County ordinance flatly bars red light cameras and speed cameras on any road, roadway or highway in unincorporated Jefferson County, Missouri. Section 105.130, enacted in…

Jefferson County requires bicyclists on any highway, roadway, or alleyway to ride as near the right side as practicable and use due care passing standing or slower vehicles. Riders get…

Jefferson County makes it unlawful to place personal property, including furniture set out during a rental eviction, on the sidewalk, roadway or any part of a county road's public…

Jefferson County requires written authorization from the Public Works Highway Division before anyone opens or excavates the public right-of-way, streets or alleys in the county. Only a…

Jefferson County prohibits all fireworks inside its county park system. Section 240.080(Q) states flatly that fireworks are prohibited in County parks, with no exception carved out for…

Smoke alarms in Jefferson County homes must be hardwired to 120-volt AC power with battery backup whenever the building has commercial electric service, under the county's amendment to…

Jefferson County shuts every County park down for the night: hours run from half an hour before sunrise to half an hour after sunset under Section 240.100, and anyone still inside once…

Reserving a pavilion, campsite, the in-line hockey rink, Big River Saddle Club equine facilities, or a Northwest Sports Complex ball field in a Jefferson County park requires a…

Jefferson County lets patrons build fires only in the fire rings and grills the Parks Department installs; bringing a personal charcoal or wood-burning barbecue grill or brazier into…

Jefferson County bars model aircraft and drones from every county park except River Bend Park in Eureka. Photographers, enthusiasts and schools who want to fly a drone elsewhere in the…

Jefferson County confines sexually oriented businesses to the PI planned industrial district and requires 1,000-foot separation from churches, schools, parks, residential zones, other…

Jefferson County lets law enforcement or county officials authorize a towing company to remove abandoned vehicles from roads, interstates, and county property without the owner's…

Jefferson County's Unified Development Order requires anyone who performs massage for compensation to hold a business license from the County and limits massage therapists to working…

Jefferson County's UDO lists "Tattoo parlor/permanent cosmetic services/body piercing studio" as a single Table 5-1 use, permitted by right in just one of the county's 15…

Jefferson County does not grade restaurants with letter cards; instead every food establishment must annually obtain, and post in public view, a County food and beverage permit from…

Jefferson County caps residential fences on the front-yard setback line at 4 feet (up to 8 feet if two-thirds open like picket or split rail in rural districts) and allows fences up to…

Retaining walls up to six feet tall, measured from finished grade to the top of the wall excluding any cap, don't need a building permit in Jefferson County unless they support a…

Jefferson County caps residential front-yard fences at four feet under UDO Section 400.2860, rising to eight feet on RA-5 and LR-2 lots with a two-thirds-open design. Rear and side…

Jefferson County bans parking within eighteen inches of any county road's traveled portion and prohibits blocking a driveway entrance or leaving less than ten feet of clear roadway on…

Jefferson County lets Public Works tow, without notice or a hearing, any vehicle situated so as to impede snow removal, construction, or maintenance operations, and the owner isn't…

Jefferson County prohibits abandoning any motor vehicle or trailer on the right-of-way of a public road or state highway, citing the state abandonment statute. The rule applies only in…

Unincorporated Jefferson County requires new or expanded retail, industrial, hospital, institutional and hotel buildings to provide on-site loading and unloading facilities…

In unincorporated Jefferson County, residential parking is confined to the driveway, an adjoining paved pad, or a legally permitted public street. Parking on grass, gravel, dirt or any…

Unincorporated Jefferson County limits recreational vehicle and boat-trailer parking in R-20, R-10, R-7, PR-1 and PR-2 residential districts to paved spaces built to fit the vehicle…

Jefferson County allows a permanent accessory dwelling unit, such as a mother-in-law cottage, in residential zoning districts with its own building permit, but it must meet the main…

Jefferson County caps combined accessory-building square footage by district under UDO Section 400.2870: up to 4,000 square feet (or 5% of the yard) on RA-5 and LR-2 lots, 1,200 square…

Jefferson County caps window signage under its zoning code: permanent signs may cover no more than 15% of a building facade's window area, and businesses may add temporary signs on an…

Jefferson County bars flashing, blinking or animated signage countywide but carves out programmable electronic message boards. On-premise boards may run a steady message with limited…

Jefferson County lets residents post yard and garage sale signs without a permit, but caps them at twelve square feet and limits their display window: no earlier than sunrise on the…

Jefferson County allows political signs without a permit if they stay at or under thirty-two square feet, or ninety-six square feet along State lettered or numbered routes, and are…

Jefferson County confines new billboards to parcels touching a short list of major routes: Interstate 55, U.S. Highways 61 and 67, and State Highways 30, 141 and 231. A billboard…

Jefferson County designates historic landmarks and districts by County Council ordinance after Historic Preservation Commission review. Once a property is nominated, no building…

Jefferson County lets single-family developers in five rural and low-density districts trade dedicated open space, parks, or public buildings for smaller minimum lot sizes and up to a…

A building permit is required before installing a residential swimming pool in unincorporated Jefferson County unless the pool is prefabricated and less than 24 inches deep. The Code…

New development in unincorporated Jefferson County must plant street trees along its frontage: one tree for every 75 feet of street frontage in most zoning districts, or every 50 feet…

Jefferson County's UDO groups food trucks with off-site outdoor produce stands and farmers' markets in one Table 5-1 use entry. In the unincorporated county's 15 zoning districts, the…

Jefferson County exempts a home occupation sign from its usual sign-permit process under UDO Section 400.4250(A)(7), as long as it is non-illuminated and no larger than 12 square feet…

Jefferson County lets residents run a home occupation under UDO Section 400.2890, but caps it at 33% of the dwelling's floor area, one non-resident employee, and no outside appearance…

Jefferson County requires a home occupation to keep traffic, parking, sewage and water use within what's normal for a residential neighborhood under UDO Section 400.2890. Deliveries…

In unincorporated Jefferson County, a residence where someone cares for up to four people at a time is a permitted accessory use under UDO Section 400.2850, no conditional use permit…

Jefferson County lets billboards along its approved highway corridors light their faces electrically, but Section 400.4310(A)(7) bans any flashing, blinking or intermittent lighting on…

Any building in unincorporated Jefferson County with structural failure, fire hazard, blocked egress, or six months of unsafe vacancy is deemed a "dangerous building" and declared a…