St. Charles County, MO Public Conduct: Outdoor Smoking Restrictions (2026)
Key Facts
- Outdoor buffer
- 15 feet from entrances, windows, vents
- Adopted
- Ordinance No. 18-070, Aug. 27, 2018
- Applies
- Countywide, incorporated and unincorporated
- Enforcing agency
- Dept. of Public Health
- Smoker fine
- Up to $50 per violation
- Business fine
- $100 to $500 per violation
- Patio exception
- Open-air, 2 or fewer solid walls
Summary
St. Charles County's Smoke-Free Air Act of 2018 doesn't stop at the doorway: Charter § 10.803.4 bans smoking within 15 feet of any entrance, operable window, or ventilation system of an enclosed area where smoking is already prohibited, and the buffer applies countywide, incorporated and unincorporated alike. Open-air patios with no more than two solid walls are carved out, as long as the smoke doesn't drift back inside.
Smoking shall be prohibited in outdoor space within a distance of fifteen (15) feet outside entrances, operable windows, and ventilation systems of enclosed areas where smoking is prohibited. "Entrance" shall mean an entryway primarily used by the public as a means to enter or exit a public place from a public street or public sidewalk.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4863880; v61 updated 2026-05-11; through 05-11-2026).
Full Breakdown
Voters approved the Smoke-Free Air Act of 2018 as St. Charles County Charter Article X, §§ 10.800-10.811, enacted by Ordinance No. 18-070 on August 27, 2018. Section 10.803.1 bans smoking inside every building and vehicle the County owns, leases, or operates, plus the outdoor space within fifteen feet of that building's entrances, operable windows, and ventilation intakes. Section 10.803.2 extends the enclosed-space ban to bars, gambling facilities, health care facilities, hotels, membership clubs, restaurants, retail stores, and sports arenas countywide, and § 10.803.4 applies the same fifteen-foot outdoor buffer to every enclosed public place where smoking is barred, defining "entrance" as a doorway the public uses from a street or sidewalk. Section 10.803.5 makes Subsections (C)(1) through (C)(4) apply "in the unincorporated area and within an incorporated municipality within St. Charles County," so the fifteen-foot rule reaches the City of St. Charles, St. Peters, O'Fallon, and every other city in the county, though a city may add its own tighter outdoor restrictions.
The Act carves out open-air patios, porches, and decks with no more than two solid, floor-to-ceiling walls, so smoking there is allowed as long as the smoke doesn't drift back into a no-smoking enclosed area (§ 10.804.6). Owners and operators must post International No-Smoking signage at the outdoor locations the Department of Public Health designates (§ 10.805.2), and every entrance sign must state that smoking is prohibited.
Violations & Fines
A person caught smoking within the fifteen-foot buffer or another banned outdoor area commits an infraction carrying up to a $50 fine (§ 10.808.1). An owner, manager, or operator who fails to enforce the buffer or post required signage faces graduated infractions: up to $100 for a first violation, $200 for a second within a year, and $500 for each one after that, plus possible suspension of the business's County permit or license (§ 10.808.2-.3). Each day of noncompliance is a separate violation, and the Department of Public Health can also seek an injunction to abate it as a public nuisance.
Frequently Asked Questions
Can I smoke on a restaurant patio in St. Charles County?
How close to a building entrance can I smoke outdoors?
Does the outdoor smoking buffer apply inside cities like St. Charles or O'Fallon too?
Who enforces the Smoke-Free Air Act outdoors?
Sources & Official References
Other rules in St. Charles County
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