We've flushed out a great deal - spend just a penny on this 0% credit card and you'll get a £30 M&S voucher, plus access to a decent 0% deal too.

There's no cheaper way to borrow than for free, which, when used right, is what a 0% 'for purchases' card allows. And now M&S effectively pays you to get its card, with a £30 voucher. Full options are outlined in our Top 0% Cards guide - but here's the key info...

19mth 0% borrowing with £30 M&S voucher + £5 of points

Accepted new M&S credit card* holders who apply by 20 June via this specific link* and spend anything, anywhere on it (even 1p) by 31 July get sent a £30 M&S voucher.

Plus the first time you use the card to buy most things at M&S (including food), you get 500 M&S points worth £5. So use the card to buy a Tesco banana and you're £30 up - use it to buy an M&S banana and it's £35. Then just pay it off.

Will it affect my credit score?

Don't just apply – instead check your chances first via our free eligibility calc (a 70%+ chance is good, 40%+ is OK).

Of course, if you then actually apply it does leave a footprint on your file. This is wiped after a year and is usually trivial, unless you make many other applications in close proximity. Yet if you're imminently due to make a big credit application (eg, a mortgage), it's probably not worth it.

When will the voucher come?

It's usually sent within a few weeks but it's promised by 22 August at the latest. You must use it by 31 August to spend in-store or online on food, clothes, homeware, flowers etc (see T&Cs).

Is the 0% deal worth using?

You should always be careful with new borrowing, but if you need it, there’s no cheaper way than 0% - just ensure it’s planned and the repayments are budgeted for.

The M&S card is good, but not table-topping. The longest 0% spending deals are Sainsbury's* 27 months (eligibility calc) and the Post Office's* 27 months (eligibility calc) - Clydesdale* (eligibility calc) and the AA* (eligibility calc) offer 26 months.

These are all 18.9% rep APR after the 0%. The M&S card gives 1 M&S point per £1 spent in M&S and per £5 spent elsewhere too, so if you can repay within the 19 months, it's a good deal.

0% Spending Card Golden Rules

See full help & best buys in 0% Spending Cards (APR Examples) - in brief:

a) Don't just apply - first find cards you've the best odds of getting via our free eligibility calc to protect your credit score.
b) Never miss paying at least the monthly min or you can lose the 0% (and always stick within the credit limit).
c) Plan to clear the card before the 0% ends (or do a balance transfer) or the rate jumps to the rep APR.
d) These cards are usually ONLY cheap for spending, not balance transfers or cash withdrawals - so avoid these.

This article first appeared in the weekly email on 4 May 2016. It was fact-checked and updated on 10 May 2016.