Skip to main content
CityRuleLookup
Key FactsOrdinance TextFull BreakdownViolationsFAQSourcesMore in Brown County

Brown County, WI Noise Ordinances: Vehicle Noise (2026)

Some Restrictions
Compiled from the official code textEditor Martyn O'NeillLast verified September 2026

Key Facts

Chapter 39 exemption
§ 39.01(6)(m): noise created by motor vehicles
Condition on exemptions
Reasonable steps taken to minimize the noise emitted
Conduct ban
§ 340.0011: unreasonably loud revving, horn, backfire
First offense
Forfeiture of $10 to $200 plus prosecution costs
Repeat within two years
Forfeiture of $50 to $300 plus prosecution costs
Jail on default
Up to 10 days first offense, 30 days second
Excluded
Legitimate, scheduled racing events

Summary

Brown County, Wisconsin's noise code, Chapter 39, exempts noise created by motor vehicles from its decibel limits in § 39.01(6)(m). Loud driving behavior is policed instead under traffic code § 340.0011, which bans unreasonably loud revving, horn blowing and engine backfire, with a first-offense forfeiture of $10 to $200.

City-specific rules exist: Green Bay, Ashwaubenon, and De Pere have their own vehicle noise rules that differ from Brown County's county-level regulations. If you live in one of those cities, check the city-specific page instead.

(6) EXEMPTIONS. The following activities shall be exempt from the regulations of this section, provided reasonable steps are taken to minimize the noise emitted. ... (k) Disorderly Conduct. Noises created by human behavior and generally considered to be disorderly conduct under other laws and ordinances. ... (m) Motor Vehicles. Noise created by motor vehicles.

View official code

Full Breakdown

Brown County, Wisconsin splits vehicle noise between two chapters, and the split matters. Chapter 39 (Noise Control, revised 5-1-2002) sets octave-band and A-scale decibel limits for residential, commercial and industrial zones, with separate daytime (7:00 A.M. to 10:00 P.M.) and nighttime (10:00 P.M. to 7:00 A.M.) tables. Section 39.01(6) then lists activities that are exempt from those limits, provided reasonable steps are taken to minimize the noise emitted. Paragraph (m) reads simply "Motor Vehicles. Noise created by motor vehicles." A muffler, stereo or engine that is merely loud is therefore not measured against the Chapter 39 tables. The same list also exempts, in paragraph (k), noises created by human behavior that are considered disorderly conduct under other laws and ordinances, which points a reader to the traffic code.

That other ordinance is Chapter 340, the county traffic code (revised 3-10-2015). Section 340.0011 prohibits any person, within the County of Brown, from causing or provoking disorderly conduct with a motor vehicle, and it names automobiles, trucks, motorcycles, minibikes and snowmobiles. The definition covers operating a vehicle in a way that is violent, unreasonably loud, dangerous to persons or property, or otherwise against the public peace, welfare and safety. The listed examples are unnecessary, deliberate or intentional spinning of the wheels, squealing of the tires, revving or racing of the engine, blowing of the horn, causing the engine to backfire, and raising one or more wheels off the ground. Legitimate, scheduled racing events are specifically excluded.

Scope: this is county code, so it governs the unincorporated towns of Brown County. The City of Green Bay, the City of De Pere and the incorporated villages such as Ashwaubenon, Bellevue, Allouez, Howard, Hobart and Suamico run their own codes inside their boundaries. Chapter 340 is enforced under Wisconsin Statutes §§ 345.20 through 345.53 and Chapter 299, as § 340.0010 states.

Violations & Fines

Under § 340.0011(3), a person found guilty can be required to forfeit not less than $10 nor more than $200, plus the cost of prosecution, for a first offense. A second or subsequent violation within two years carries a forfeiture of not less than $50 nor more than $300, plus costs. Unpaid forfeitures can lead to confinement in the County Jail for up to 10 days on a first offense and up to 30 days on a second.

Frequently Asked Questions

Does Brown County set a decibel limit for car stereos or mufflers?
Chapter 39 does not apply its decibel tables to vehicles. Section 39.01(6)(m) exempts noise created by motor vehicles, and the exemption list is conditioned on taking reasonable steps to minimize the noise emitted. Conduct with a vehicle that is unreasonably loud is instead reached by the disorderly conduct rule in § 340.0011.
Is revving an engine or honking a horn illegal in Brown County, Wisconsin?
Yes, when it is unnecessary, deliberate or intentional. Section 340.0011(2) lists revving or racing of the engine, blowing of the horn and causing the engine to backfire as examples of disorderly conduct with a motor vehicle, alongside squealing tires and wheel spinning. The conduct must be unreasonably loud, dangerous or otherwise against the public peace.
What is the fine for loud vehicle conduct in Brown County?
A first offense carries a forfeiture of not less than $10 nor more than $200 plus the cost of prosecution. A second or subsequent violation within two years carries not less than $50 nor more than $300 plus costs. Failure to pay can mean up to 10 days in the County Jail for a first offense and 30 days for a second.
Does the county rule apply inside Green Bay or De Pere?
No. Brown County's code governs the unincorporated towns. Green Bay, De Pere and the incorporated villages, including Ashwaubenon, Bellevue, Allouez, Howard, Hobart and Suamico, adopt and enforce their own noise and traffic ordinances within their limits, so check the municipal code for a vehicle stopped or driven inside one of them.
Are racing events covered by the disorderly conduct rule?
Legitimate, scheduled racing events are specifically excluded from the definition in § 340.0011(2). The exclusion covers organized events only. Revving, tire squealing or racing the engine on a public road outside such an event still falls within the definition of disorderly conduct with a motor vehicle.

Sources & Official References

Other rules in Brown County

Quiet HoursSome RestrictionsConstruction HoursSome RestrictionsAnimal Ordinances: Dog Leash LawsSignificant RestrictionsDecibel LimitsSome RestrictionsAmplified Music & Outdoor SoundSome RestrictionsAircraft NoiseSignificant RestrictionsBarking DogsFew RestrictionsParking Rules: Abandoned VehiclesSome RestrictionsFence Regulations: Fence Permit RequirementsSome RestrictionsLandscaping Rules: Tree Removal & Heritage TreesSome RestrictionsLandscaping Rules: Native PlantsSome RestrictionsCurfew Laws: Juvenile CurfewSignificant Restrictions

All Brown County rules

Compare Brown County to another location·View the Wisconsin noise ordinances overview

Get notified when Vehicle Noise in Brown County, WI changes

We'll email you the moment we detect a change in the code. No spam, unsubscribe anytime.

We'll never sell or share your email. One-click unsubscribe in every email.

See something wrong?

Help us keep this page accurate. If you notice an error or outdated information, let us know.

Vehicle Noise in Cities Across Brown County

Ashwaubenon, WIDe Pere, WIGreen Bay, WI