Don't pay double with swipe-cards

Consumer watchdogs have warned people who carry two or more Octopus cards in their wallet - watch out, when you beep, it won't be cheap.

The Consumer Council said the finding came after a complaint from a woman who ran two Octopus cards stored in her wallet over an Octopus reader on a minibus.

The screen displayed the remaining balances of both the woman's cards.

According to operator Octopus Cards Limited, in such cases two things may happen - either the transaction may not go through at all or the sum may be deducted from both cards.

'The latter case happened because the reader failed to differentiate whether the two cards had been used together or if two card holders had used their cards in rapid succession,' said Professor Ching Pak-chung, vice-chairman of the council's publicity and community relations committee.

'Everyone has at least one Octopus card. But if you have two, try not to put them together in your wallet or handbag to avoid being overcharged.'