It will also increase the number of flights from Belfast to Heathrow from seven a day to eight. The airline said it had no plans to expand their operations to Cork or Shannon.
Simon Daly, BA sales manager for Ireland, said that including the code share agreement between Aer Lingus and BA there would be 20 flights a day between Dublin and Heathrow.
The eight new daily BA flights are as a result of International Airlines Group (IAG) acquisition of BMI. They mean BA is returning to Dublin airport after a 20-year absence.
BA’s taking over of the BMI route will see the airline going into direct competition with Aer Lingus on this route for the first time.
Vincent Harrison, Dublin Airport Authority’s director of strategy, welcomed the BA move.
“This is excellent news for business and leisure travellers, as BA’s doubling of its existing Heathrow service will offer additional choice and flexibility for passengers. Dublin-London is Europe’s busiest international city pair with 3.7m passengers travelling by air between the two capitals last year.”