The bank joins Santander and Barclays among major banks blocking U.K. customers from purchasing crypto on Binance.
The bank has seen a "high level" of crypto investment scams, a company spokesman said.
This follows HSBC stating it would not be facilitating exposure to Coinbase or any other crypto-centric business.
NatWest, part of Royal Bank of Scotland, has joined Marco Polo, a blockchain consortium started by R3 and trade finance specialist TradeIX.
Stealth project Cordite, led by the Royal Bank of Scotland, promises the equivalent of an ERC-20 token standard for R3's open-source Corda platform.