From 1 April 2017, we will be unable to accept cash payments at London Heathrow, London Gatwick and many of the airports we operate from in North America. This includes all types of payments, such as for extra bags, additional/exit row seats, changes to tickets, service charges, etc.
Please advise customers who cannot pay with a credit or debit card to check with a member of our staff at the airport to find out if options are available for converting cash to a payment card as this varies by airport:
• At London Heathrow, customers can buy a Multi-Currency Cash Passport from Travelex that they can use to pay instead.
• At many North American airports, customers can either buy a Multi-Currency Cash Passport from Travelex, or use Cash-to-Credit card kiosks to convert cash into a prepaid debit card for a $5 charge per transaction. Any charges associated with the use of a cash conversion machine are collected by the company who owns and operates the machine.
Important note:
Please advise customers who use a prepaid debit card to not throw it away until their travel is complete, even if the card is empty. If we need to refund any costs, we will be returning these to their original form of payment.
From BA Website