Stobart Air is to operate new flights on behalf of British Airways CityFlyer from London City airport.
The regional carrier run by Southend airport owner Stobart Group already operates franchise flights for Flybe and Aer Lingus.
The new agreement will see Stobart Air provide aircraft, crew, maintenance and insurance services for BA CityFlyer.
The arrangement will see Stobart Air provide the services to operate London City routes under the BA CityFlyer brand from November 16.
Stobart Air also plans to add 40 new staff by recruiting ten captains and first officers as well as 30 cabin crew.
The carrier will lease two Embraer 190 regional jets under a three-year lease agreement with Ireland-based Nordic Aviation Capital to serve the new routes.
Stobart Air managing director Graeme Buchanan said: “A key part of our growth strategy is to secure additional commercial relationships with airlines.
“This agreement with BA CityFlyer allows us to further diversify the brands we work with.
“Stobart Air is recognised within the industry for its operational excellence and quality of customer service, and this deal demonstrates that we can continue to leverage this reputation to grow our business and secure further commercial relationships.”