BT Payphones and Travelex UK are testing a new style of phone box fitted with both a cash machine and a telephone.
The Travelex branded red, white and blue kiosks feature a cash machine on the exterior of one side and a payphone on the other side of the box. Installations will be concentrated in areas where there is no cash machine nearby, say the companies.
Trial boxes have been installed in Sutton in Surrey, Southend in Essex, and Portsmouth, with a further five sites in central London also lined up. If the pilot is successful, then up to 300 of the kiosks will be rolled out across the country from April this year.
Paul Hendron, director of BT Payphones, says the aim is to attract people into payphones and generate new revenue to help maintain and develop the network.
Charges for use of the phone box cash machines will vary depending on the location, he adds.
For security purposes, a DNA traceable, indelible powder stains everything including the cash, if an attempt is made to steal from the kiosk.
BT already operates a network of 1500 public Internet Kiosks in UK high streets, shopping centres, tube, rail and bus stations. These "blue boxes" can be used for payphone calls, surfing the web, sending e-mail, text, photo and video messages.