Littlewoods has been criticised for offering interest-free deals that could leave customers paying double the price of some rival stores.
The online site allows customers to pay on a weekly basis, over 20 weeks for any product and a year for products costing £100 or more.
"If you're after the latest brands or you want to buy something really, really special, our interest-free weekly payments can help make things affordable today, simply because you don't have to pay the whole amount up front," the company claims.
But there's affordable, and there's affordable. Many Littlewoods products are so highly priced that customers are paying dear for their Buy Now Pay Later (BNPL) deals.
A Barbie Malibu house, for example, costs just £49.99 from Amazon. Buy it from Littlewoods, though, and you'll be paying £1.92 every week for a year - adding up to a whacking £99.84.
"It is a disgusting rip-off. I had no idea Littlewoods had gone into the payday loan business, but clearly they have," Marc Gander, of the Consumer Action Group tells the Sun.
"It's a scandal they can't be more upfront. What a shame they are taking advantage of poor people so they end up having to pay through the nose for the rest of the year."
"Littlewoods customers benefit from a range of flexible payment options to help spread the cost of purchases – a simple offer that they tell us they really value and that we've been providing for more than 80 years."
Littlewoods is by no means the only catalogue company to offer interest-free deals. And even when products aren't being sold at inflated prices, they can still cost customers dear.
Which? warned consumers earlier this year that there are big charges to pay if customers fail to make their payments - with Littlewoods not only slapping interest on products at an APR of 36.9%, but also backdating that to the time or the order, rather than the delivery.
"Some 'buy now, pay later' deals may charge you interest on the whole balance even if you're just a single day late in repaying, so always check the small print and repay on time to avoid hefty penalty fees," said Which?'s Gareth Shaw.
Cheaper - but equally risky - is to choose a new credit card on a 0% interest deal and make purchases using that. It means customers can shop around for the lowest price so that they're not tied to a particular catalogue company. Most credit cards also charge a lower interest rate than catalogue companies once the interest-free period ends.
Safest and cheapest of all is to save up for things before you buy them, rather than after.
Read more on AOL Money:
The danger of 'buy now, pay later' shopping
What really damages your credit rating
Interest free credit cards: five top tips