An interest-free balance transfer credit card from Virgin Money launches today, which can be cheaper than the longest 0% deal.

The Virgin Credit Card offers 0% for 16 months with a 1.5% fee on debts shifted, only via price comparison site

In contrast, the Barclaycard Platinum card offers 0% for 20 months – the longest interest-free balance transfer deal around – but it has a higher 3.2% fee which is what makes it pricier in some cases.

However, which is best depends on how much you can repay each month and what your debt is.

For instance, on a £3,000 debt if you pay £130 a month it will take two years to pay at a cost (in interest and fees) of £101 on Barclaycard or £107 on Virgin.

If you pay £160 a month, it takes 20 months at a cost of £59 on Virgin and £86 on Barclaycard.

The reason Virgin can be cheaper in some cases is due to a combination of its lower fee and the fact that if you pay more off, you have less of a balance left when interest is charged.

This means its higher APR of 18.9%, compared to Barclaycard's 17.5% is less of a problem as interest is levied on the balance at the time.

This shows that the market is so complicated, meaning it is difficult to judge the best card based on the headline rate alone. Our Which card's cheapest? tool works out the best plastic based on your circumstances.

Remember, if you only pay the minimum you'll be stuck with the debt for years.