The system, called Silent Solutions, has been used by the Metropolitan Police for almost a year to screen out such calls made in London.
More than two million silent calls have been successfully dealt with and £3 million saved thanks to the new system.
Nearly half of all emergency calls made from mobiles are accidental and it has caused a huge headache for police and other emergency services.
All silent calls, where the caller does not specify the emergency service they require, are automatically forwarded to local police forces.
Press five
Under the Silent Solutions system, all silent calls received by the 999 switchboard are automatically forwarded to an automated service.
The service plays a recorded message informing the caller that they have been connected to the police at New Scotland Yard.
The message informs the caller that if they require either the police, ambulance, fire brigade or another emergency service they must press the number five on their keypad twice.
If this action is taken the call will be reconnected as a priority to an operator but in the vast majority of cases there is no response and the line is disconnected.
All of the calls are recorded.
"It's a very important facility to have especially at the Met which has to deal with an enormous number of calls and needs something sophisticated," said a spokesperson for ACPO (Association of Chief Police Officers).
"So many false calls are made without the user knowing," he added.
Accidental knocking
The growth of mobile phone use has had a dramatic impact on call handling.
In order to cope with the increase in calls, the Metropolitan Police is receiving £140m of government money to overhaul its 999 call centres, reports Computing magazine.
The aim of the project is to improve the processes behind the 999 service as the number of calls increases.
The central communications information room at New Scotland Yard receives an average of 8,500 emergency calls each day.
Silent Solutions has intercepted around 2,000 calls a day, freeing up valuable police resources to deal with real emergencies.
Since introducing the system, the number of calls answered within 15 seconds has risen from 53% to over 88%.
The majority of accidental emergency calls are made through the knocking of the mobile phone keypad when it is in a bag or pocket.
A European Union directive makes it mandatory for owners to still be able to dial an emergency service even when the keypad on a mobile phone is locked.