British Telecommunications Plc has announced a series of price changes for its Integrated Services Digital Network service. According to the company, firms that opt for three, four and five year contracts for both the ISDN 2 and ISDN 30 services, will gain discounts on rental charges. These will range from 3%, 7% and 10% respectively, says British Telecom. The company also announced that quarterly rental charges on ISDN 30 will increase by 3.2%, from ú33.87 to ú34.95. ISDN 2 is to remain at ú84.00. Finally, British Telecom announced that the takeover charge on existing ISDN installations has been cut from ú50 to ú17 for ISDN 2, and that a new tariff for ISDN 30 has been introduced. The latter will be fixed on a per channel basis of ú8.50 per channel (from six channels). Same day takeover for both services is free.