Banking giant NatWest has imposed stricter rules on cryptocurrency transfers to protect customers after £329m was lost by UK consumers last year.
The bank is imposing a daily limit of £1,000 and a 30-day payment restriction of £5,000 on exchanges.
It comes in the wake of the collapse of the crypto exchange FTX, which was estimated to have had 80,000 UK customers.
NatWest is setting the rules implementing the rules to “help protect customers losing life-changing sums of money”.
Men over 35 are at risk because they are willing to take risks, said NatWest.
The cost-of-living crisis is also having an impact with promises of high returns used by criminals to entice investors.
Spokesman Stuart Skinner said: “We have seen an increase in the number of scams using cryptocurrency exchanges and we are acting to protect our customers.
“You should always have sole control of your cryptocurrency wallet and nobody else should have access. If you didn’t set the wallet up yourself or can’t access the money then this is likely to be a scam.”