Who Decides What Counts as Green Aviation Fuel?

UK ETS Authority seeks views on sustainable aviation fuel treatment, with carbon compliance and SAF incentives hanging in the balance

18 Jun 2026

A regulatory consultation launched on 23 March 2026 could fundamentally reshape how sustainable aviation fuel is treated under UK carbon markets. The UK ETS Authority opened the process seeking views on fuel eligibility, sustainability criteria, emissions thresholds, and how the scheme interacts with the UK SAF Mandate. Any changes that result are expected to take effect by 2028.

Central to the debate is a proposed reduction in the greenhouse gas savings threshold, from 65% to 40. That shift would meaningfully expand which fuels qualify under the scheme, easing entry for emerging pathways that currently fall short. According to the UK ETS Authority's consultation document, "The approach adopted following the consultation will have direct implications for carbon compliance costs and the commercial incentives to produce and use SAF." Broadening eligibility could accelerate adoption by opening the market to a wider range of producers and blending technologies.

Divergence from EU emissions trading frameworks adds another layer of complexity. Ongoing ETS linking negotiations between the UK and EU remain unsettled, and any deliberate misalignment on SAF treatment carries real commercial weight for operators on transatlantic and intra-European routes. The UK Department for Transport is closely involved, given its parallel responsibility for the SAF Mandate requiring increasing fuel blending across domestic aviation.

Responses were due by 15 June 2026. The consultation window is now closed. Attention shifts to the Authority's analysis, with industry participants watching closely for signals on whether a lower threshold and wider fuel scope survive into final policy. Carbon cost structures built around these decisions will shape SAF investment for years. Businesses that engaged in the process are positioned to influence a framework defining sustainable aviation's commercial trajectory well into the decade ahead.