Revolut, which has around 25 million customers worldwide, the vast majority of whom are in the U.K. and EEA, is rolling out the service this week, AltFi said. At first, the London-based fintech will support staking of the tokens of Polkadot (DOT), Tezos (XTZ), Cardano (ADA) and Ethereum (ETH). Yields on the assets range from 2.99% up to 11.65%, though these are variable.