The letter of intent will see the airline buy 20 777-9s and 19 787-10s as part of a programme of growth and modernisation taking place over the next decade.
The 787-10s will be available from the 2020/21 financial year while the 777-9s will be due for delivery from the following financial year.
The deal also gives the airline the option of substituting the 787-10 orders for other variants of the 787 family.
Singapore Airlines chief executive Goh Choon Phong said: “Today’s major order for widebody aircraft enables us to continue operating a modern and fuel-efficient fleet, providing the SIA Group with additional expansion opportunities to ensure that we retain our industry-leading position.
“We are continuing to invest for the future of the SIA Group. This order is also another demonstration of our commitment to further growing the Singapore hub, as we will be able to offer even more travel options for our customers.”
The order is the first of the airline group’s for the new 777 variant which is currently under development while it will also be the launch customer for the 787-10.
In addition to the 30 previously-ordered 787-10s, SIA has outstanding orders with Airbus for five A380-800s and 57 A350-900s.
