British Airways (BA) is generally considered moderately strict compared to low-cost carriers, but they have firm rules regarding baggage dimensions and weight. In 2026, BA is quite generous with hand luggage, allowing one cabin bag (up to 56 x 45 x 25 cm) and one personal item (up to 40 x 30 x 15 cm), with a weight limit of 23 kg per bag. While they rarely weigh carry-on bags unless they look visibly overstuffed, they are strict about size; if your bag does not fit in the sizer, it will be checked into the hold, potentially for a fee if you are on a "Basic Economy" (hand baggage only) fare. For checked luggage, they strictly enforce the 23 kg or 32 kg limit depending on your class of service; even a single kilogram over can trigger a heavy bag charge (typically around £65). They are also meticulous about boarding groups, ensuring passengers board in the specific order listed on their digital passes to maintain cabin efficiency.