Weekend Money tallied the partridge, the pear tree, the white swans (black ones would have been a lot cheaper), a day's milking from a farmhand and the services of the Williamstown RSL Pipe Band, among other things, to find out how much the gifts in the Christmas carol would cost.

The carol repeats the previous day's gifts and adds a new one as each day goes by, but we reckoned no one's ''true love'' would want 12 partridges in 12 pear trees - no matter how much they welcomed your attentions - so we kept it simple (see table).

We then asked financial products researcher RateCity to work out how long it would take to pay off the $25,042 total, assuming you had a rewards-linked card (as you would if you went around spending that sort of money) and paid only the minimum required each month.

It turns out, with a card charging 19.42 per cent interest (the average for a rewards card), and a minimum repayment of just 2.35 per cent of the balance (again average), the debt would take 42 years to clear, at a cost of $52,650 in interest.

And that doesn't include the $135 annual fee you would pay for the average points-based credit card.

The $180 in shopping vouchers RateCity estimates you would earn on the average rewards card for that spending hardly compensates for an interest bill of $4702 in the first year alone.

The bottom line is you would still be paying for Christmas 2012 in 2054.

As unlikely as that might seem, it's a fact that three-quarters of the collective debt on our credit cards is rolled over each month - about $35 million out of the $49 million outstanding at the end of the month. At an interest rate of 20 per cent, that's about $7 million in interest a year.

It's true Australians have become more reluctant to use credit cards. But card balances have their usual spike in February, even during the worst of the global financial crisis, as the bills arrive for gifts and holidays bought in December and January.

And it's at this time of year, Reserve Bank data shows, that people leave a bit more on their cards for payment next time.

''We've seen how pre-Christmas shopping on expensive credit cards can make for a very unhappy new year,'' says Penelope Hill, the advice services manager at MoneyHelp, a financial counselling service run by the Consumer Action Law Centre.

To make sure Christmas cheer lasts throughout the year, we've pulled together holiday advice from consumer and financial groups. This year, much of the advice focuses on online shopping, over which there's concern about how easy it is to tick and click, as well as the potential for the theft of personal information for financial fraud.

Don't fall for the glitter

Hill of MoneyHelp says giving gifts is one of the most rewarding parts of the holiday season, but people should look out for sales gimmicks aimed at getting them to spend more than they planned. ''Take a deep breath before typing in your credit card details, and consider your financial position before buying,'' she says.

Make a list and check it twice

Set a budget for Christmas spending, write a shopping list of gifts and treats, then stick to it. Even if it's not your habit, keep a record of your card spending and check the daily total against your budget.

Think twice before applying for more credit

It may be tempting, but if you couldn't afford a higher credit limit last month, can you afford it now?

Protect your personal information

''Christmas shopping online can be convenient, easy and find terrific bargains,'' says the senior manager for fraud and financial crimes at Abacus Australian Mutuals, Leanne Vale. ''But make sure you know the seller is legitimate, you are confident in the product purchased and your credit card details are protected.'' Provide card details only to secure sites that have the symbol of a locked padlock in the browser.

Don't forget your phone

Most people are aware of the need to have security software installed on their computers, but with smartphones just as likely to be used for banking and shopping, we need firewalls, antivirus protection and strong passwords for these devices as well. ''It's particularly important to ensure shopping using your mobile phone or other digital devices is safe,'' Vale says. See staysmartonline.gov.au.

Tell your bank about your travel plans

If you're taking advantage of the strong Australian dollar and going overseas, tell your bank and give them your contact details, the Australian Bankers Association says. The bank needs to know there's a logical explanation for those transactions in New York, and how to reach you if they suspect fraudulent activity on your account.

Use the card extras you've paid for

The number of credit cards offering ''premium services'' has doubled in the past year, says a RateCity spokeswoman, Michelle Hutchison. One of the most popular additions is the ''price guarantee scheme'', under which cardholders can claim a refund of the difference between what they paid for an item and the cheaper price if it goes on sale. These cards have annual fees of $100 to $150, and have interest rates as high as 23 per cent, so make sure they earn their keep. Also check if your card insurance covers the excess for insurance on your rental car.

Know your rights

Under Australian consumer law, goods must be of acceptable quality and fit for their purpose. If there's a major defect, the consumer - not the supplier or manufacturer - gets to choose whether they want a refund, replacement or repair. If the defect is minor and can be repaired, the consumer cannot demand a refund but can ask the supplier to fix the problem. It's up to the supplier to offer a refund, replacement or repair. People who receive goods and services as gifts have the same rights as consumers who buy direct.

❏ By the way, if you were to follow The 12 Days of Christmas to the last turtle dove, the total cost would be $119,240 - and you would probably be accused of stalking.