Last reviewed April 22, 2026
About
Train Horn Hub
Reference · Reviews · Since 2026
State Law · Wyoming (WY)

Wyoming Train Horn Laws 2026 — Wyo. Stat. §31-5-957 Explained

Wyoming train horn law (Wyo. Stat. §31-5-957): vehicle horn rules, Cheyenne / Casper enforcement, aftermarket horn regulations. Plain-English guide.

By Train Horn Hub editors Published April 22, 2026 Updated April 22, 2026
Status
Legal
Vehicle Code
Wyo. Stat. §31-5-957
Last reviewed: April 22, 2026

Disclaimer. This page summarizes publicly available Wyoming statutes as of April 2026. Not legal advice. Verify and consult a licensed Wyoming attorney.

Quick facts
Legal status
Legal
Install permitted
Statute
§31-5-957
Wyo. Stat. Title 31
Audibility required
200 ft
Factory horn minimum
Specific dB cap
None
"Unreasonably loud" test
Siren/whistle/bell ban
Yes
Emergency exempt
Penalty
Misdemeanor
Fine

Installing an aftermarket train horn on a private vehicle in Wyoming is not prohibited. Wyoming train horn law is in Wyo. Stat. §31-5-957 — “Horns and warning devices.” Standard UVC pattern: 200-ft audibility, “unreasonably loud or harsh sound” ban, use limited to safe-operation cases, sirens/whistles/bells barred on non-emergency vehicles.

Install is legal; use on Wyoming public roads — Cheyenne, Casper, Laramie, Gillette, Rock Springs, Sheridan, Jackson — is the regulated behavior.

What Wyo. Stat. §31-5-957 actually says

§ Statutory excerpt

Every motor vehicle when operated upon a highway shall be equipped with a horn in good working order and capable of emitting sound audible under normal conditions from a distance of not less than two hundred (200) feet, but no horn or other warning device shall emit an unreasonably loud or harsh sound or a whistle. The driver of a motor vehicle shall when reasonably necessary to insure safe operation give audible warning with his horn but shall not otherwise use the horn when upon a highway. No vehicle shall be equipped with nor shall any person use upon a vehicle any siren, whistle or bell, except as otherwise permitted in this section.

— Wyo. Stat. §31-5-957 — Horns and warning devices Wyoming Legislature · Title 31 →

Operative rules: 200-ft audibility · no unreasonably loud or harsh sound or whistle · no siren/whistle/bell (emergency exempt) · safe-operation use limit · theft-alarm exception.

Does the factory horn need to stay working in WY?

Yes. §31-5-957 applies to the vehicle as a whole.

Is a train horn a “whistle” under §31-5-957?

How §31-5-957 reads warning devices
∿
Prohibited
Siren · whistle · bell
  • ·Siren — variable-pitch tone
  • ·Whistle — single-tone pressure device
  • ·Bell — fire / warning bell
  • ·Unreasonably loud or harsh language
♪
Train horn (chord)
Not enumerated
  • ·Multi-note chord, not a whistle tone
  • ·Install not banned
  • ·Use subject to "unreasonably loud" test
  • ·Factory horn must remain functional

Portable and battery-powered train horns in WY

§31-5-957 regulates “a horn or other warning device” — power source agnostic. M18, DeWalt 20V, Ryobi, Makita portables fall under the same rules.

Enforcement in practice

Wyoming is broadly permissive — the least-enforcing tier. Cheyenne, Casper, and Jackson see complaint-driven enforcement; rural counties with the lowest population density in the contiguous US rarely cite anything short of documented misuse.

Scenario · What happens if you're stopped for a train horn in WY
Step
01
Initial contact
WHP or local officer observes misuse / receives complaint
Install alone rarely triggers stops.
Step
02
Primary question
Did horn emit 'unreasonably loud or harsh' or a whistle/siren/bell?
§31-5-957 tests.
Step
03
Factory horn check
Is OEM horn working at 200 ft?
Equipment violation if disconnected.
Step
04
Outcome
Misdemeanor · fine
WY traffic equipment offenses default to misdemeanor.

Practical Wyoming train horn compliance

If you install a train horn in WY
6 steps
  1. 01
    Keep factory horn wired and functional

    200-ft rule applies to the vehicle.

  2. 02
    Put the train horn on a separate switch

    Distinct from OEM button.

  3. 03
    Use factory horn for ordinary signaling

    Safe-operation limit per §31-5-957.

  4. 04
    Reserve use for off-road / ranch / BLM / private property

    Wyoming has vast BLM, ranch, and national-forest land.

  5. 05
    Watch Cheyenne / Jackson / Casper ordinances

    Municipal noise codes layer on state law.

  6. 06
    Hearing protection when testing

    140+ dB causes immediate damage.

How to verify this page

Verify on the Wyoming Legislature Title 31 PDF. Send a correction if needed.

Primary Source · Page Capture
Screenshot of the official statute page at wyoleg.gov
Visit source
Wyoming Legislature — Title 31 Chapter 5 (official portal) · wyoleg.gov captured April 22, 2026

Nearby states & related laws

All 50 states →
CO Legal

Colorado

C.R.S. §42-4-224

Colorado CRS §42-4-224 covers vehicle horns. Install is not prohibited; use is limited and sound must not be harsh. Plain-English statute summary.
MT Legal

Montana

MCA §61-9-401

Montana train horn law (MCA §61-9-401): vehicle horn rules, Billings / Missoula enforcement, aftermarket horn regulations. Plain-English guide.
SD Legal

South Dakota

SDCL §32-15-10

South Dakota train horn law (SDCL §32-15-10): vehicle horn rules, Sioux Falls / Rapid City enforcement, aftermarket horn regulations. Plain-English guide.
NE Legal

Nebraska

Neb. Rev. Stat. §60-6,285

Nebraska train horn law (Neb. Rev. Stat. §60-6,285): vehicle horn rules, Omaha / Lincoln enforcement, aftermarket horn regulations. Plain-English guide.

Sources & Citations

Educational content. Not legal advice. Verify current statutes with your state DMV or a licensed attorney before installation.