British Airways is widely considered one of the more generous airlines regarding hand luggage, but they have become increasingly strict about where that luggage goes. Every passenger is allowed two pieces of cabin baggage for free: one large cabin bag (56x45x25cm) and one smaller personal item (40x30x15cm). While they rarely weigh hand luggage—provided you can lift it into the overhead bin yourself—they are very strict about dimensions. If a bag appears oversized, gate agents will require you to place it in a sizer; if it doesn't fit, it must be checked into the hold, potentially for a fee if your ticket is a "Basic" (hand baggage only) fare. On busy flights, BA is known for proactively asking passengers to check their larger cabin bags at the gate for free to save space in the overhead lockers. However, your smaller personal item is "guaranteed" to stay with you in the cabin, provided it fits under the seat in front of you. This makes them less stressful than low-cost carriers, but you should still ensure your bags meet the official measurements to avoid last-minute gate disruptions.