Jet A-1 is a kerosine grade of fuel suitable for most turbine engined aircraft. It is produced to a stringent internationally agreed standard, has a flash point above 38C(100F) and a freeze point maximum of -47C. It is widely available outside the U.S.A. Jet A-1 meets the requirements of British specification DEF STAN 91-91 (Jet A-1), (formerly DERD 2494 (AVTUR)), ASTM specification D1655 (Jet A-1) and IATA Guidance Material (Kerosine Type), NATO Code F-35.

Jet A is used in the United States while most of the rest of the world uses Jet A-1. The important difference between the two fuels is that Jet A-1 has a lower maximum freezing point than Jet A (Jet A: –40°C, Jet A-1: –47°C). The lower freezing point makes Jet A-1 more suitable for long international flights, especially on polar routes during the winter.