A reward of up to £100,000 is being offered for information which leads to the conviction of armed bank robbers in Greater Manchester and Merseyside.
The reward has been offered by the British Bankers' Association, for information given to Crimestoppers.
The crime-fighting charity operates an anonymous telephone number, and is not part of the police.
It said the issue of bank robberies went beyond cash being stolen - staff and customers are being attacked.
Gary Murray, Crimestoppers' North West regional manager, said: "Armed robbers are committing atrocious crimes, threatening and sometimes using violence to steal money. Nobody should be allowed to get away with this.
"We understand people can be fearful of giving information about criminals. That's why we operate a service where people can pass on information about crimes and criminals without revealing their identity, which means they will never speak to police or go to court.
"All they need to do is make a phone call, and that could help get an armed robber locked away so they can't commit further armed robberies."
Crimestoppers is also putting posters on phone booths, distributing beer mats and posters for newsagents and post offices in Greater Manchester and Merseyside.