Block’s Afterpay is the unexpected leader of the US “Pay in 4” installment market, holding 38% of total loan value in 2025, according to a New York Fed study. Block is also the largest BNPL provider by total credit issued, originating $53.7B for a 34% share and edging out Affirm, which trails by more than $12B at 26% despite being an earlier mover. eMarketer reads the win as validation of Afterpay’s strategy, since Cash App has long courted underbanked consumers with alternative underwriting and its own credit score, and bundles BNPL into a full stack of banking, P2P, lending, and debit that makes its app stickier than rivals built around BNPL alone. One caveat, the Fed study left out card-linked installments, a chunk of the market consumers actually prefer over standalone BNPL, per PYMNTS.
