The low-cost carrier made the announcement to help mark its 15th anniversary at Belfast International Airport (BIA).
From summer 2014 easyJet will introduce new flights to Jersey in the Channel Islands and Bordeaux in south west France. Seats for both routes go on sale next month.
EasyJet has flown more than 32 million passengers to and from BIA since it introduced its first flight to Luton 15 years ago.
There is currently no direct flight from Northern Ireland to the Channel Islands. Ali Gayward, the airline's head in Northern Ireland, said the new routes offer a range of new holiday and business connections. "Since we launched our first flight to Belfast in 1998 over 32 million people have chosen to fly with us," she said.
"Today we're saying thank you to all those passengers who have helped make easyJet Northern Ireland's largest airline.
"Belfast was one of our first bases outside Luton and we look forward to celebrating many more anniversaries here."
EasyJet has six aircraft based permanently at BIA and employs over 200 crew and pilots there.
More than three million people fly to and from the Belfast hub with easyJet annually.
John Doran, BIA managing director, said the airline carries more passengers into and out of Northern Ireland than any other.
"One of the main reasons for their success is that easyJet provides low fares to the destinations to which both business and leisure passengers want to travel," he said.
"EasyJet singularly changed all of that, as well as adding direct access to European cities from Belfast, and for that alone the Northern Ireland public owe them a huge debt of gratitude."
He added: "In this 50th anniversary year of Belfast International Airport we would like to wish easyJet a very happy 15th birthday in Northern Ireland."
Gerry Lennon of Visit Belfast said: "We wish easyJet continued success and we look forward to greeting thousands more visitors in years to come."
Timeline: How easyJet took off at Belfast International:
September 1998: First easyJet flight arrives
July 1999: New route introduced to Liverpool
October 2000: easyJet increase flights between Northern Ireland and England
January 2001: New service to Amsterdam introduced
October 2001: New services to Glasgow and Edinburgh
October 2002: easyJet establishes a base in Belfast
February 2003: New services added to Newcastle and Gatwick
June 2004: Significant growth in international routes
November 2007: Sixth aircraft arrives at Belfast and five new routes launched