UK operator Virgin Atlantic is signing for up to 20 Airbus A330neo twinjets, with an initial eight firm aircraft and another six being taken from US lessor Air Lease.
Virgin is also taking options on a further six of the twinjet type.
Deliveries will take place over the course of 2021-24.
Virgin Atlantic will use the -900 version of the re-engined aircraft to replace Airbus A330-300s and -200s.
All A330-900s are powered by Rolls-Royce Trent 7000 engines.
"Return to growth is crucial and critical for us," said Virgin Atlantic chief executive Shai Weiss, speaking during a Paris air show briefing.
He says the order is part of the airline's "biggest fleet transformation" which includes the delivery shortly of the carrier's first A350-1000 – one of 12.