The order is for the A350-900, and includes options for 20 additional aircraft, which would increase the value of the order to $14 billion. Airbus said the deal allows SIA to select either the baseline A350-900 or the larger A350-1000 variant when exercising the options.
Placing this latest order increases SIA's total firm orders for the A350 to 70, excluding options. The order comes as the carrier looks to overhaul its fleet with more fuel-efficient aircraft and expand its regional network, as well as push into begin competing in the budget airlines market.
Airbus is on schedule to conduct the first flight with the A350 later this year, with entry into service in the second half of 2014.
"As we move closer to first flight, demand for the A350 XWB continues to grow, especially for the larger models," said John Leahy, chief operating officer at Airbus.
A total of 34 customers worldwide have placed more than 600 orders for the A350.