When Affirm filed to go public, its biggest merchant was Peloton. The bike maker made up about 28 percent of Affirm's revenue, because shoppers split the price of a bike into monthly payments. Max Levchin, a PayPal co-founder, built Affirm as an honest alternative to the credit card. It showed the total cost up front and charged no hidden fees. Affirm listed in January 2021, as pandemic shopping moved online.

A PayPal Founder's Second Act

Levchin co-founded PayPal and later sold his photo-sharing company, Slide, to Google. In 2011 he started HVF, a lab for data-heavy companies, and Affirm spun out of it in 2012. The bet was that a lender could judge each purchase on its own, with better data than a credit score. Merchants paid Affirm to offer the loans, because shoppers bought more. By September 2020 it had 3.9 million active consumers.

Nearly Double on Day One

Affirm priced its offering at $49 a share in January 2021 and sold 24.6 million shares. The stock nearly doubled on its first day on Nasdaq, as investors bet that online shoppers would keep paying in installments. Buy now, pay later became a crowded field. Affirm signed deals with Amazon and Shopify, and the stock swung hard as interest rates rose. Levchin remained chief executive. Affirm still trades on Nasdaq as AFRM.

Cover: The Maid Shopping, Camille Pissarro. Art Institute of Chicago, public domain. Chosen for a shopper at the market (buy now, pay over time).