EFTPOS error 51

In the early days of credit cards people often only used them for the occasional one-off big purchase like a holiday, or maybe even a new television. Today it is more common for people to use their credit cards instead of cash, and for transactions as small as fuel purchases, or a weekend takeaway.

At some point in your life you will go through the slightly embarrassing experience of having a card transaction declined. If this happens locally, and you have another method of payment, it will an inconvenience and nothing more. However, if you are in a foreign country, and only have your credit card on you as a method of payment you could have a real problem.

Use this guide to discover why your credit card transaction may have been declined and what you can do to avoid rejected purchases in the future.

Why was my credit card transaction declined?

To be certain of the exact reason your credit card transaction was declined, you need to speak to your credit card company. However, these are some of the common causes:

If your card provider notices strange patterns in your spending habits they may well put a block on your credit card for security purposes. For example, if you only ever use your credit card a couple of times a week for very small purchases, and then in one day there are 3-4 large purchases made, your issuer may flag the activity as strange or potentially fraudulent and will block the card.

Some credit cards have daily spending limit within the terms and conditions. If you have not read your terms properly you may not be aware of these and this could result in you overspending and having a transaction declined.

If you're planning to use your credit card overseas, you should contact your card provider to let them know beforehand. If your issuer sees a range of transactions happening overseas, they might suspect it's a fraudulent payment and block your card.

EFTPOS machines use the phone network to communicate with the banks to verify and authorise your transactions. If there is a system outage at the point of sale or with the bank's server, the transaction may be declined. If this is the case, you may be asked to sign the tax invoice for authorisation.

• Exceeded your credit limit.

Every credit card comes with a maximum credit limit that you shouldn't exceed. While some credit cards let you spend beyond the credit limit and will charge you a fee, others will simply decline the transaction if you spend beyond the limit. If you require more credit, you can find out how to increase your credit limit with our guide.