These cards don’t charge any interest on your spending for a set period. That way you can pay off the balance in more manageable chunks, safe in the knowledge that every penny you pay is going directly towards clearing your debt rather than on interest charges.

And the good news is that Halifax has just launched the longest 0% deal ever!

Pay no interest for 20 months

The Halifax Purchase Credit Card comes with a 20-month 0% period. To put that into context, if you took it out today, you wouldn’t start paying interest on your balance until April 2016. That’s an awful long time in which to clear that balance.

However, you will want to clear the balance before interest begins being charged, as it carries a representative APR of 18.9%.

Not everyone who is accepted for the card will be offered a 20-month 0% period though. While more than half of successful applicants will get the headline interest-free period, other applicants may be offered a 16 month 0% period instead, as well as a higher representative APR of 21.9% or 25.9%.

How it compares

Halifax is now the clear market leader when it comes to lengthy 0% purchase periods. However, as the table below demonstrates, there are plenty of alternatives if you need at least a year in order to clear your balance.

While the Tesco Bank Clubcard Credit Card for Purchases offers one month less of 0% interest, it does reward you with Clubcard points on your spending. You get five points for every £4 spent in-store, and one point for every £4 spent everywhere else, so if you’re a regular Tesco shopper it may be worth going for.

The Santander 123 Credit Card is another 0% card that offers something extra. You earn cashback on your spending. You get 1% cashback when you spend at supermarkets, 2% when you shop at major department stores and 3% at major petrol stations, on National Rail and Transport for London travel.

However, the Santander 123 Credit Card does come with an annual fee of £24, so you’ll need to ensure you earn more cashback than that to make it worthwhile.

Making the most of a 0% credit card

The big benefit of a 0% purchase credit card is that you don’t have to pay off your balance all in one go. Instead you can pay it off at a more manageable pace, without paying anything towards interest charges.

However, that shouldn’t be seen as a licence to overspend. Don’t get carried away just because you are free from interest for a while.

It’s always a good idea, once you’ve made your big purchases, to sit down and work out exactly how much you’d need to pay each month to clear the balance before interest begins being charged. Then set up a monthly standing order for that amount.