UK biodiesel supply increased by 62% in 2026, while reported sustainable aviation fuel (SAF) volumes more than doubled, rising 124% compared with equivalent reporting periods in 2025, according to provisional Department for Transport (DfT) statistics.
The latest data provide an early snapshot of renewable fuel use across UK road transport and aviation, although the two datasets cover different reporting frameworks and remain subject to revision.
Under the Renewable Transport Fuel Obligation (RTFO), around 1.99 billion litres equivalent of renewable transport fuels had been reported through the available mid-July 2026 reporting periods. This compares with approximately 1.73 billion litres equivalent during the corresponding periods of 2025, representing growth of about 15%.
Separately, suppliers reported 291.7 million litres of SAF under the UK’s SAF Mandate in data available to 1 September 2026. The equivalent 2025 reporting periods recorded around 130.1 million litres, giving a reported increase of approximately 124%.
Biodiesel and Bioethanol Show Different Growth Patterns
Biodiesel methyl ester (ME) was among the fastest-growing major renewable fuel categories covered by the RTFO.
Reported biodiesel ME supply reached approximately 545.2 million litres equivalent during the comparable 2026 periods, compared with 336.2 million litres equivalent in 2025. That represents an increase of around 62%.
Bioethanol remained the largest individual renewable fuel category in the RTFO data. Its reported volume rose from approximately 839.1 million litres equivalent to 901.6 million litres equivalent, an increase of about 7%.
Other fuels recorded contrasting movements. Compressed biomethane increased by approximately 3%, reaching 71.4 million litres equivalent, while liquefied biomethane fell by around 4% to 53.4 million litres equivalent.
HVO supply also declined. Reported volumes fell from approximately 340.4 million litres equivalent in the comparable 2025 periods to 272.4 million litres in 2026, a decrease of about 20%.
The RTFO figures form part of the first provisional release for 2026 and are based on information available to 3 September 2026. The DfT has indicated that the dataset is incomplete and will be revised as further fuel volumes and sustainability information are submitted.
Development Fuels Record Sharp Increase
Development fuels recorded another substantial rise in the provisional RTFO statistics.
Reported supply reached approximately 117.5 million litres equivalent across the comparable 2026 periods, compared with around 44.7 million litres equivalent in 2025. This represents an increase of more than 160%.
Development diesel accounted for a significant proportion of the increase, with reported volumes rising from approximately 20 million litres equivalent to more than 74 million litres equivalent.
Development fuels form a category within the RTFO intended to support emerging renewable fuel pathways.
The RTFO uses Renewable Transport Fuel Certificates (RTFCs) as a mechanism for demonstrating compliance with renewable fuel obligations. The associated statistics also record sustainability and carbon characteristics for certified renewable fuels, although certification information can be reported later than the underlying fuel volumes.
UK SAF Volumes Reach 3.92% of Reported Aviation Fuel
The provisional SAF data show a substantial increase in reported aviation fuel volumes during the 2026 obligation year.
The 291.7 million litres of SAF reported in the available 2026 dataset represented 3.92% of total aviation fuel reported.
The figure is also approaching the approximately 332.8 million litres reported for the whole of 2025 in the latest provisional dataset. However, the periods covered are not identical, so the two totals cannot be treated as a full-year comparison.
The like-for-like comparison is between the equivalent reporting periods: SAF increased from approximately 130.1 million litres in 2025 to 291.7 million litres in 2026, producing the reported 124% increase.
The SAF statistics are the first provisional release for the 2026 obligation year and use information available to 1 September 2026. As with the RTFO data, the figures will be updated as additional information is submitted and verified.
RTFO and SAF Mandate Now Operate Separately
The figures reflect the UK’s separate regulatory treatment of renewable fuels for surface transport and aviation.
Since the SAF Mandate came into force on 1 January 2025, SAF has no longer been included in the RTFO statistics. The RTFO covers qualifying renewable fuels supplied for road transport and non-road mobile machinery, while aviation fuel volumes are reported through the dedicated SAF Mandate system.
The separation means that renewable fuel trends across road transport and aviation need to be assessed using their respective datasets rather than by combining the reported volumes.
The DfT published the first provisional 2026 releases for both mechanisms on 17 September, providing an initial view of renewable fuel supply during the current obligation year.
Bioenergy Business Analysis
The provisional figures point to a mixed renewable-fuel market rather than uniform growth across all fuel types. Biodiesel ME and development fuels recorded substantial increases, while bioethanol posted more moderate growth and HVO and liquefied biomethane declined. That divergence makes the composition of renewable fuel supply as important as the headline increase in total RTFO volumes.
The sharp rise in reported SAF volumes is also significant in the context of the UK’s separate aviation-fuel mandate. However, the data remain provisional and cover only part of the respective obligation years. The eventual market picture will therefore depend on additional reporting, verification and revisions before the final 2026 datasets are scheduled for publication in November 2027.
