Half of Americans say this 'no interest' deal should be illegal

With the holiday season upon us, one personal finance site is sounding the alarm on a ubiquitous retail payment plan that many Americans say should be outlawed.

It’s called “deferred interest." In a typical scenario, the shopper puts a big purchase on a store credit card. The retailer promises to charge no interest if the buyer pays off the balance within a set time frame.

The problems start if you fail to repay the entire sum before the promotional clock runs out. At that point, the deal is off and the consumer owes every penny of deferred interest, often at a steep annual rate of 30% or more. It’s as if the promotion never existed.

Roughly half of American consumers don’t fully understand how deferred interest works, WalletHub reports in its Deferred Interest Study , published Nov.