Ending BT's directory enquiries monopoly has led to fewer people using the service, and left those that do use it unhappy about its cost, according to a report by Ofcom.
The report found that when the service was free it was used by 69 per cent of UK citizens. After the change to a commercial service, usage rates held briefly and then plunged by 48 per cent, as measured in November last year.
"The number of people using directory enquiries has fallen," Sir John Bourn, head of the National Audit Office, told MPs.
"This is partly due to confusion and perceptions of higher costs; of those using directory enquiries less frequently, one in five consumers wrongly believed that the old 192 service was free. But it is also as a result of a greater use of alternative sources of information, such as the internet."
The worst services were Orange (118000) and BT (118500) while the best value for money came from Conduit (118 888) and BT's Welsh service (118404).
BT and The Number (118118) dominate the service with 80 per cent of the market. BT's 118500 charges 51p for a 45-second call from a landline, 21 per cent more than the old 192 service. The Number is even higher, charging 56p for the same average call.
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