​Millennials and Gen Zers have an addictive new way to buy stuff that would look familiar to their great-grandparents. “Buy now, pay later” is a type of consumer credit that really got going in the 19th century when Singer sewing machines were sold for a “dollar down, a dollar a week.” But the modern fintech twist in “BNPL” is that it’s aimed at people making impulse purchases of fashion or jewellery or electronics rather than sofas or refrigerators. It’s delivered through apps that are wildly popular, leading to dizzying valuations of startups like Amazon, Zomato etc.

​Buy Now, Pay Later (BNPL) is a type of short-term financing that allows consumers to make purchases and pay for them at a future date, often interest-free. Also referred to as "point of sale instalment loans," BNPL arrangements are becoming an increasingly popular payment option, especially when...