On August 17, 2026, the California Energy Commission unanimously adopted the state's first replacement tire efficiency standards, and the exemption structure creates a genuinely strange result: a large, aggressive off-road tire has an easier path to staying on shelves than a smaller, efficiency-oriented all-terrain does. Here is what the rule actually says, not just what enthusiasts are saying about it.
What the rule actually does
The Replacement Tire Efficiency Program, adopted under authority from a 2003 law, Assembly Bill 844, sets a minimum rolling resistance standard for tires sold in California. Rolling resistance is energy lost as heat while a tire deforms and recovers with every rotation; lower resistance means better fuel economy. The rule does not regulate grip, sidewall strength, or handling. It also carries a minimum wet grip requirement so efficiency gains cannot come at the cost of braking performance.
It takes effect in two steps: Phase 1 begins January 1, 2029, with a rolling resistance ceiling of 9.0 N/kN, and Phase 2 begins January 1, 2033, tightening that ceiling to 7.1 N/kN, roughly matching what today's original equipment tires already average. The rule applies based on the tire's manufacture date, not its sale date, so the DOT date code on the sidewall determines which phase applies.
The off-road exemption, and why it matters
The large off-road tire exemption requires two things: a diameter of 34.5 inches or greater and a speed rating of Q or lower (99 mph max). Meet both, and the tire is exempt from the efficiency standard entirely.
That threshold sits well above what most Jeep and Bronco owners actually run. A stock 33-inch all-terrain, one of the most common tire sizes in the off-road world, does not qualify on diameter alone. A 37-inch mud-terrain almost always does. The practical result: owners running smaller, more efficient all-terrains are the ones most exposed to the new rule, while owners on the biggest, least fuel-efficient tires are largely exempt from a program written to improve fuel efficiency.
The other exemptions
Several more categories are carved out, some relevant to off-roaders and some not:
- Deep tread tires, 18/32 inch or greater, covering most aggressive mud-terrains regardless of diameter
- Limited production tires, under 15,000 units sold annually, reporting required but exempt from the standard itself
- Winter tires carrying the 3PMSF snow rating with a traction index of 112 or higher
- Competition and track tires, and ultra-high-performance tires rated above 168 mph
- Motorcycle tires, space-savers, run-flats, tires with a load index of 122 or higher, and anything that cannot sustain 50 mph
Between the diameter exemption and the deep-tread exemption, most genuinely aggressive off-road tires clear the bar one way or another. It is the middle ground, quieter, smaller all-terrains built for daily driving with occasional trail use, that has the fewest ways out.
What will it actually cost?
The California Energy Commission's own projections put the added cost at about $1.50 per tire in Phase 1, roughly $6 for a set of four, and $6.50 per tire in Phase 2, roughly $26 to $39 for a set depending on size. Against an estimated $179 in fuel savings over a typical four-year tire life, the commission's math works out to a payback period of around seven months.
Industry pushback tells a different story. Goodyear's representative told the commission the real increase could run into several hundred dollars per tire and estimated that roughly 70 percent of tires currently sold in California would no longer qualify. That figure comes from industry testimony, not an independently verified source, so treat it as one side's estimate rather than settled fact. The truth, as usual with projections like these, probably lands somewhere between the two.
What this means if you off-road in California
If you are running 35s or larger with a Q or lower speed rating, or a deep-tread mud-terrain in any size, this rule likely doesn't affect you. If you are on a common 32- or 33-inch all-terrain, budget for the possibility that your exact tire gets discontinued or repriced when Phase 1 lands in 2029, and expect the gap to widen when Phase 2 tightens things further in 2033.
SEMA and the Off-Road Business Association pushed the commission to loosen the exemption to 33 inches and an R or lower speed rating, which would have covered far more common all-terrain sizes. The commission declined. Whether that changes before 2029 is worth watching, and the commission itself has signaled the rule is designed to evolve, meaning today's exemptions are not guaranteed to look the same in a few years.
California is also rarely the last state to adopt a rule like this. Even if you do not live there, this is worth watching as a preview of what could show up elsewhere.
Frequently asked questions
Does California's new tire law ban off-road tires?
No. It sets a minimum rolling-resistance efficiency standard for replacement tires, with a wet-grip floor built in. It does not ban tires outright, but tires that do not meet the standard and do not qualify for an exemption cannot be sold as new replacement tires in California once each phase takes effect.
When does California's tire efficiency rule start?
Phase 1 begins January 1, 2029. Phase 2, with a stricter standard, begins January 1, 2033. The rule applies based on the tire's manufacture date, not the date it is sold.
Are 35-inch tires exempt from California's tire rule?
Tires 34.5 inches or larger with a Q speed rating, 99 mph, or lower qualify for the large off-road exemption, so most 35-inch off-road tires meet that bar. Smaller tires do not qualify on diameter alone, regardless of speed rating.
Will this make off-road tires more expensive in California?
The California Energy Commission projects a modest increase, about $1.50 per tire in Phase 1 and $6.50 in Phase 2, offset by fuel savings. Industry representatives have projected a much larger increase. Neither figure is independently confirmed, so actual pricing will depend on how manufacturers respond.
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