While maximum size of main carry-on bags will remain unchanged at 56x45x25cm, smaller second bags such as handbags will be capped at 40x30x15cm instead of the current 45x36x20cm from August 18, the British Airways said in a statement.
"We know that customers want their flights to leave on time, so we are looking at a number of initiatives to help us maintain punctuality.
“We are asking customers to help us achieve this by adhering to our hand baggage allowance, which is clearly stated on ba.com," the airline said.
"We will continue to offer a generous two bag allowance.
“The dimensions of the cabin bag will remain the same, while we are reducing the size of the second, laptop or handbag, so that it will fit underneath the seat in front.
“Customers will always be able to take this bag on board, even if the flight is very busy," it added.
Currently, passengers can board flights carrying one bag of up to 56x45x25cm, weighing up to 23kg, plus another bag up to 45x36x20cm.
Economy and premium economy travellers will be affected by the change, although those in first class will be exempted, it added.
Image: British Airways. Photograph: Reuters
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