Arizona Truck Idling Law
Arizona has no single statewide limit. State law (ARS 11-876) requires every county containing part of "Area A" — Maricopa plus the Area A portions of Pinal and Yavapai — to adopt a heavy-duty diesel idling ordinance. In practice both Maricopa County (Ordinance P-21) and Pinal County set a 5-minute limit for diesel trucks over 14,000 pounds, with fines of $100 first and $300 after (the 5-minute figure comes from the county ordinances, not the statute). Outside the Area A counties there is no enforced idling time limit.
When you can keep idling
- Traffic or adverse weather
- DOT-mandated rest (49 CFR 395)
- Manufacturer warm-up or cool-down
- Maintenance and repair
- PTO work
APUs and idle-reduction gear
Use an APU instead of the main engine to comply. Idle-reduction tech also earns up to a 550-pound weight allowance (ARS 28-1100).
City and county ordinances
- Maricopa County (metro Phoenix): diesel over 14,000 lbs, 5 minutes, $100 first / $300 repeat (Ordinance P-21).
- Pinal County (Area A portion — Apache Junction / Gold Canyon on the US-60 corridor): diesel over 14,000 lbs, 5 minutes, $100 first / $300 repeat (Area A Vehicle Idling Ordinance).
Arizona Idling Law FAQ
Is there a truck idling law in Arizona?
How long can a truck idle in Arizona?
What is the fine for idling in Arizona?
Does an APU count as idling in Arizona?
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 Traffic laws change and this can be out of date, so always confirm the current statute and obey posted signs before you rely on it.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=AZ. See our Terms & Disclaimer.
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