When flying BOS→LGW in May, you’ll see a mix of legacy carriers (typically offering full-service onboard amenities, baggage inclusion, and premium cabins) and seasonal/low-cost operators (competitive base fares with a la carte extras). Legacy carriers often include meals and checked baggage in transatlantic fares, while low-cost options may charge separately for seat selection, bags, and onboard service. If you prioritize comfort and fewer fees, a legacy carrier or premium economy product is preferable; if price is the primary concern, compare total trip cost including baggage and seat fees.