St. Louis County, MO Fire Regulations: Fire Pits & Backyard Fires (2026)
Fire pit rules in St. Louis County, MO, also called outdoor burning, recreational fire, or open flame ordinances, cover fuel types, clearances, and when burning is allowed.
Key Facts
- Approved fuel
- Only untreated, seasoned dry firewood
- Base area cap
- 9 square feet maximum, all fires combined
- Smoke rule
- No visible smoke, ash, or soot past property line
- Permit needed
- None, if the three conditions are met
- Max penalty for violation
- $1,000 fine and/or 1 year in county jail
Summary
St. Louis County allows backyard recreational fire pits without a permit, but only if the fire burns pure untreated, seasoned dry firewood, its base area stays at nine square feet or less, and no smoke, ash, or soot drifts visibly past the property line. It's one of the few exceptions carved out of the county's blanket open-burning ban.
Recreational fires:
i. Recreational fires shall be comprised of only untreated seasoned dry fire wood which is free of leaves, needles, yard waste, garbage, rubbish, treated wood, or tree trimmings; and
ii. Total cumulative base area of the fire(s) shall not exceed nine (9) square feet; and
iii. The recreational fire shall not cause smoke, ash, or particulate matter to remain visible in the air or upon surfaces beyond the property line where the fire is occurring.
b. Preparation of food, such as barbecuing:
i. Fires shall either be contained through recreational food preparation equipment, such as a grill, rotisserie, outdoor cooking stove, or other device constructed for the use in outdoor, noncommercial food preparation; or
ii. Total cumulative base area of the fire(s) shall not exceed nine (9) square feet; and
iii. The fire shall be comprised of only untreated seasoned dry fire wood or charcoal which is free of leaves, needles, yard waste, garbage, rubbish, treated wood, or tree trimmings; and
iv. The fire shall not cause smoke, ash, or particulate matter to remain visible in the air or upon surfaces beyond the property line where the fire is occurring.
c. Burning conducted for natural resource conservation purposes:
i. Fires shall meet the requirements for a prescribed natural resource burn either through the collaboration with and subsequent development of a natural resource conservation
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 85 | Traffic: Supplement 80).
Full Breakdown
345's countywide open-burning ban, and it comes with three specific conditions rather than a permit process. First, the fuel is limited to untreated, seasoned dry firewood, free of leaves, pine needles, yard waste, garbage, rubbish, treated lumber, or tree trimmings; manufactured fire logs and treated materials aren't approved fuel for a recreational fire. Second, the fire itself, counting every burning pile if more than one is going at once, cannot cover more than nine square feet of base area; that cap is the same one used for backyard barbecue fires but half the sixteen-square-foot allowance given to seasonal yard-waste burns on large rural lots.
Third, the fire cannot send visible smoke, ash, or particulate matter drifting past the property line, a nuisance-style test that a neighbor's complaint or an inspector's observation can trigger regardless of how compliant the fuel and size are. There's no minimum lot size or setback distance written into this exception the way there is for yard-waste burning, and no separate permit or fee to obtain from the Air Pollution Control Program before lighting a compliant recreational fire. 390: up to $1,000, up to a year in jail, or both, with each day counted separately.
Violations & Fines
A recreational fire that burns treated wood, yard waste, or garbage, exceeds the nine-square-foot base area cap, or sends visible smoke or ash past the property line loses its exemption and is treated as illegal open burning. Enforcement runs through the chapter's general penalty, Section 612.390: up to $1,000, up to a year in county jail, or both, per day of violation.
Frequently Asked Questions
Do I need a permit for a backyard fire pit in St. Louis County?
Can I burn yard waste or pallets in my fire pit?
How big can my fire pit be?
Sources & Official References
Other rules in St. Louis County
How St. Louis County compares: Cities with the Strictest Fire Pit Rules·Compare St. Louis County to another location·View the Missouri fire regulations overview
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