Tracking fuel among US airlines and their fleets

You have read it here several times: fuel is ~45% of operating costs for US airlines. Hence, the race to update fleets to chase the latest in engine technologies, along with wingtips and any other fuel-saving ideas.

The number for 1Q25 is 47%, as shown in the model below. The model is concise, comprising only four pages, and provides an excellent overview of fuel burn by airline and aircraft type. The model focuses on single-aisles as this is the industry bedrock.