“Could a UK high-street bank build a credible standalone digital challenger to Monzo and Starling? (Answered: no.)”
Bó was RBS/NatWest's attempt at a consumer digital challenger bank, launched in late 2019 to counter Monzo and Starling. It never scaled — reaching only ~11,000 customers, mostly friends-and-family — and was hit by a compliance glitch requiring mass card reissuance and a wave of senior departures. RBS announced its wind-down in Q1 2020, folding the technology into its SME challenger brand Mettle. Bó is a canonical example of a traditional bank failing to spin up a competitive digital-only bank.