Boulder Municipal Airport could begin offering unleaded aviation fuel as early as late 2026, according to a newly submitted state‑mandated transition plan.
According to the Boulder Reporting Lab, five Colorado public airports were required to deliver plans by January 1, 2026, outlining how they will phase out leaded aviation fuel by 2030.
Boulder’s draft calls for an annual review to update the strategy as fuel technology and regulations evolve. However, the plan does not yet specify which unleaded fuel will be offered, what infrastructure will be needed, or how costs will be covered. Officials expect those details to be finalized in the coming months.
To encourage pilots to make the switch, the airport is exploring incentives such as reimbursing costs for Supplemental Type Certifications needed for some aircraft and state subsidies to offset higher fuel prices. Longer-term plans could include installing a 10,000-gallon self-service tank dedicated to unleaded avgas.
Boulder’s initiative is part of a broader effort to reduce aviation lead emissions. The FAA’s EAGLE initiative (Eliminate Aviation Gasoline Lead Emissions) aims for a nationwide transition to unleaded fuel by 2030, and Boulder’s timeline would put the airport ahead of many others — though technical and financial hurdles remain.
Other Colorado airports are moving quickly as well. Rocky Mountain Metropolitan Airport (KBJC) recently made UL94 available, with two flight schools already committed. RMMA officials say the fuel is compatible with roughly two-thirds of the piston-engine aircraft based at the airport.
Centennial Airport was the first in the state to offer UL94, introducing the fuel in 2023. In May, the airport said it had reimbursed 105 STC applications and has seen UL94 account for more than 20.5% of all aviation fuel for piston aircraft sold at the airport since its introduction. However there have been reports that several pilots have reverted back to avgas after experiencing overheating issues during summer flights.
Meanwhile, public feedback on Boulder’s plan will be gathered through quarterly noise abatement meetings and tenant discussions, with officials promising updates as fuel technologies and community input evolve.
