Late payers will soon face much larger fines in the U.K. in what is promised to be the “toughest crackdown on late payments in a generation.” The scheme, announced by Business Secretary Jonathan Reynolds on July 30, is intended to save the 38 businesses a day that go bust because of poor payment practices.

Ruth Prickett graduated from Cambridge University with a BA hons in History and has specialized in business and finance journalism for the past 20 years. She was editor of Financial Management, the magazine...