The question doing the rounds in air cargo right now is blunt: is ReFuelEU Aviation's sustainable aviation fuel mandate finally working? That question — posed this week by Air Cargo Week — cuts to the heart of the cost equation for every carrier lifting freight out of Europe.

The honest answer is that the source material raising the question does not settle it. What it does do is put the debate back on the table at a moment when shippers are watching fuel surcharges closely and carriers are watching their compliance paperwork pile up. So it's worth taking the question apart. What does "working" even mean here?

What does the mandate actually require?

ReFuelEU Aviation, the regulation that entered into force across the EU, obliges fuel suppliers at Union airports to blend SAF into their jet fuel deliveries. The obligation starts low and climbs on a fixed schedule, ramping toward much heavier blends by mid-century. Airlines, in turn, must uplift a share of their fuel at EU airports rather than tankering in cheaper unblended kerosene from outside the bloc.

That second lever matters more than it looks. Without an uplift requirement, carriers could simply fill up beyond EU borders and sidestep the blend. The mandate closes that door.

Who pays, and how fast?

SAF still costs multiples of conventional jet fuel. Every blended litre lands in the price of fuel, and the fuel surcharge lands on the air waybill. For forwarders, that means European origin freight is quietly getting a green premium baked into the rate card. For carriers, it means a compliance cost that competitors outside the EU don't carry — unless, and until, equivalent regimes such as those discussed in the UK and elsewhere level the field.

The mechanism is simple. The consequences ripple. Fuel is the largest single operating cost for most freighter operators, and a percentage-point shift in the blend translates into a measurable shift in cost per tonne-kilometre.

Is it working? The open verdict

Here the source is candid by omission: the piece poses the question rather than declaring victory. The debate it frames turns on supply. Mandates create demand on paper; whether refinery and renewable-fuel capacity is actually delivering blended volume at EU airports — and at what price — is the number everyone wants and nobody publishes cleanly yet.

For air cargo specifically, the stakes differ from passenger flying. Freighter economics run on thinner margins per kilo. A fuel-cost shock that a passenger network absorbs can push a freighter rotation from profitable to marginal in a single quarter.

What should shippers and forwarders watch?

Three practical markers will tell you whether the mandate is genuinely functioning rather than merely existing:

• Blend volumes actually delivered at major EU hubs, not just obligated volumes on paper
• Surcharge behaviour — whether carriers itemise the SAF component or bury it in the general fuel surcharge
• Divergence on competing lanes, especially if non-EU hubs keep offering unblended fuel at a discount

Each one is checkable. Each one turns the abstract question into a number.

The verdict, for now, is unresolved — but the direction of travel is not. ReFuelEU's blending steps only get steeper from here, and every carrier flying freight out of Europe will be pricing that climb into its 2025 contracts.

Tom Whitfield