Passengers travelling through 19 British airports will be allowed to carry two pieces of cabin luggage through security checks starting on Monday, the government said.
Airports where the one cabin bag restriction is being lifted include Heathrow, Stansted, London City, Manchester, Cardiff, Birmingham and Aberdeen, the Department of Transport said.
Airports where the one bag rule will stay in place for weeks include Gatwick, Luton, Leeds Bradford and Liverpool.
Airport operator BAA PLC recommended travellers check with airline to see what carryon baggage policy is in place at their departure airport.
Transport Secretary Ruth Kelly said last week improved security technology meant the restrictions could be relaxed.