Refunds are expected to take around 30 days to process and money will be refunded to the original form of payment.
Rob Burgess, editor of the frequent flyer website Head for Points, said: “Perhaps I’m being cynical, but British Airways seems to be making the process more complicated than is necessary.
“For a start, you cannot cash in your eVoucher until two years from the date it was issued.
“It is important to note that your flight must have been cancelled. If you voluntarily choose to take an eVoucher for a flight which was operating, you are not entitled to cash in your voucher.