Idaho Truck Idling Law
Idaho has no statewide idling time limit, and a 2024 law (HB 533) went the other way. It spells out that a commercial truck may idle for heat or AC while the driver rests (including via an APU), and a parked reefer may idle to protect a perishable or pharmaceutical load, as long as the truck has a working muffler. The law is written to override local idling ordinances, though the resort towns of Ketchum and Hailey have their own 3-minute limits.
When you can keep idling
- State law protects idling for heat or AC while a driver rests, including via an APU
- A parked refrigerated truck may idle while laden with perishable goods or pharmaceuticals to protect its load
- The truck must have a working muffler
APUs and idle-reduction gear
No statewide rule.
City and county ordinances
- Ketchum limits idling to 3 minutes in any 60-minute period ($25 fine, Ketchum Code ch. 8.09); nearby Hailey has a similar 3-minute ordinance.
Idaho Idling Law FAQ
Is there a truck idling law in Idaho?
How long can a truck idle in Idaho?
What is the fine for idling in Idaho?
Does an APU count as idling in Idaho?
Reference information for planning, not legal advice. Traffic laws change and this can be out of date, so always confirm the current statute and obey posted signs before you rely on it. Last reviewed July 2026. Source: https://afdc.energy.gov/fuels/laws/IR?state=ID. See our Terms & Disclaimer.
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