The airline now operates a fleet of 101 A380's and estimates that almost 900 million passengers have flown on its flagship aircraft.
Sheikh Ahmed bin Saeed al-Maktoum, chairman and chief executive of the Emirates Airline, signed the memorandum of understanding (MoU) earlier Thursday with John Leahy, chief operating officer customers of Airbus Commercial Aircraft, at the airlines' headquarters in Dubai.
Emirates has committed to buy 20 planes, with an option for 16 more, in a deal that would be worth up to $16bn (£11.5bn) at list prices, although the Gulf airline will have negotiated a substantial discount. Last year Emirates celebrated the 100th delivery of the iconic jet and ten years since its first delivery.
His Highness Sheikh Mohammed bin Rashid Al Maktoum, Vice President and Prime Minister of the UAE and Ruler of Dubai, said: "Emirates truly represents Dubai's spirit of growth, innovation and resilience".
At Dubai's biennial Air Show in November, Airbus suffered an embarrassment when it was scheduled to announce it had a struck a deal with Emirates for its A380, only to see Boeing sit on the podium with the airline and sign a $15.1 billion deal.
Airbus's decision in 2007 to pursue the A380, capable of packing in 853 seats, was diametrically opposed to Boeing's bet on the Dreamliner, marketed as a more efficient plane that could be used for both medium and long-distance flights.
Already by far the biggest A380 customer, Emirates had repeatedly stalled on the follow-on deal, putting the future of the double-decker in doubt after it failed to win any new orders for two years.
Leahy told reporters Monday that Emirates is the only airline with the ability to commit to a minimum of six planes a year for a minimum of eight to 10 years, or what is needed to make the Airbus program viable. "It will be a great relief to Airbus to have secured this order, but they have to work aggressively to secure orders from other airlines too now". By way of comparison, Boeing's rival 787 Dreamliner had 94 orders a year ago.