The long-awaited announcement from Delta finally came in June: Boston is now officially a hub for the airline's operations. It's the carrier's first new hub since 2014, when they announced their intentions of landing at Seattle, to open up a whole new array of transpacific routes and city services that Delta never had access to before from the west coast.
Similar to how Alaska Airlines, which is ironically based in Seattle, initially gave Delta tough competition in the airport market share at SEA, the same seems to be happening in BOS with its rival airline JetBlue. The latter has the majority of the market share in terms of passengers transported to/from the airport. Delta has already announced a plethora of new routes, both domestic and international from Boston including to Amsterdam, Dublin, Edinburgh, Lisbon, London (both Heathrow and Gatwick), Paris, Chicago, Washington D.C., Manchester, and Rome. These include joint ventures with Virgin Atlantic and SkyTeam partner Alitalia.
Delta sees the opportunity to open up Boston as a secondary gateway to Europe, in order to, not only avoid the congestion of the main New York airports (JFK, LGA, and EWR), but also to try and grab some of the market share along with their code-share partner, Virgin Atlantic, from JetBlue, after it announced their new transatlantic routes from Boston to London in 2021 with the deliveries of their A321LR's.
Planned growth for the region includes daily departures to peak at around 150 by the Spring of 2020.
The airline has been experiencing continued growth in the airport as they gain more airport landing slots and gates, with Delta expected to become the sole airline operating in terminal A, which will free up 21 extra gates by September 2019. In 2021, the airline is also said to have 31 gates in terminal C, which is also JetBlue's own terminal, and they hope to have increased their daily departures by 40%, from 150 up to 200, by the same year.
While JetBlue currently sees more total daily departures, and serves more total passengers across more destinations, they also have ambitious plans for growth to a planned 200 daily departures They are vying to stay ahead of Delta as the airport's top air carrier. It should be interesting to see how much of a fight Delta gives them in competing for the market share in the near future, and if any dynamic changes to the airport or either airline happen to further that change.