Unauthorised transactions can occur for a number of reasons. Credit card issuers have put in a lot of effort to minimise the effect of these transactions.
There are a large number of transactions that can constitute an unauthorised transaction. These include a fraudulent use of a stolen card. There may be a genuine misunderstanding or crossed wires as the wrong credit card details are used or mistaken for another credit card. There may also be compromised credit card details that have either come from hacking of the issuer’s computer or network or they may have been obtained through an email “phishing expedition”.
If any of these things happen then a card will need to be cancelled and replaced with a new card. This can be quite inconvenient, particularly if this came about through some sort of fraud that was done through the details being stolen from a bank or a shopping site. In these cases then the card will need to be replaced for any regular payments that are currently made on the card. This can mean that a couple of payments are late, although in most cases replaced cards is seen as quite a normal occurrence as long as it is dealt with quickly.
Both VISA and MasterCard operate a zero liability guarantee. This means that they will not allow an unauthorised transaction to be charged against a card user’s account if the card user tells them in good time and that the card user does not contribute to the problem.
This is another good reason for the card user to read their monthly credit card statement with some care each month. If unauthorised transactions are spotted at this time and are notified to the bank as soon as they are found then they will fall under the zero liability guarantee.
It is also important that the card holder does not contribute to the unauthorised transaction. This can include such things as letting people know the card numbers, not adequately checking a person’s identity when they call asking for the credit card details or lending the card to use, even if the card was to be used for something else.
Card companies are doing a number of things to prevent unauthorised transactions. This includes using chip and pin technology and internet identity checking as well as scrutinising client credit accounts for suspicious transactions.

