The year-round service will operate up to three times a week on Tuesdays, Thursdays and Sundays.
Birkir Holm Guðnason, Icelandair CEO said: "Icelandair is proud to welcome Belfast on board as our latest UK gateway, working again in partnership with our sister airline Air Iceland Connect who will operate the service. This addition improves our connectivity and enables us to carry even more passengers to our 18 gateways across the US and Canada, via our hub in Reykjavik."
The new Belfast route is operated by Air Iceland Connect on its 72 seat Bombardier Q400 aircraft in a code sharing partnership with Icelandair, offering connections at Keflavik International Airport in Iceland to destinations in the US and Canada through Icelandair‘s network.
Brian Ambrose, chief executive of George Best Belfast City Airport, added: "This is a hugely exciting period for Belfast City Airport following our recent co-hosting of the Routes Europe conference, and the launch of our new three-times weekly flight to Reykjavik will help continue the positive momentum."
The flight from Belfast to Reykjavik provides connections with Icelandair’s network of destinations in the US and Canada.
Icelandair also began flights to new destination Philadelphia on 30 May 2017, operating four times a week from Reykjavik to Philadelphia until 20 September 2017. Flights from all seven UK gateways will connect to this.
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