Up until 8 years ago, BT had a monopoly in the directory enquiries market with its 192 service. Then, in a move that was designed to lower costs for consumers, Oftel (now Ofcom) opened up the market to competing firms in August 2003.

Last year, Ofcom began a consultation into the simplification of non-geographic numbers (including 118 numbers), which was focused on improving consumer confidence in these services. The consultation closed in March, and the data that was gathered indicates that consumers often underestimate the charges associated with directory enquiries calls.

According to Ofcom, 66% of consumers believe directory enquiries calls cost under £1. In fact, the average cost from a landline is £1.75, and it’s more than £2 from a mobile. A typical 45-second landline call to 118 118 costs £1.61, compared to a cost of £1.88 for the same call to BT’s 118 500. O2 users pay £1.53 for a 45-second directory enquiries call, and T-Mobile users pay £2.04.

If you ask (or, more realistically, agree) to be connected to the number you have requested, you can end up paying a lot more, and the charges vary radically depending on which service you’re using. Ofcom has reported that in 2009 a consumer was billed £350 for a 118 call and connection to another number!

Free directory enquiries service 192.com conducted its own research, which found that a 5-minute conversation connected from a 118 500 call costs £8.83 from a landline. The same call through 118 118 comes in at £3.71. It’s mobile users who are getting the roughest deal, however – a 5-minute call after being connected by directory enquiries on T-Mobile will cost you a fairly ridiculous £12.24. The same call costs £12 with Vodafone, £8.80 with O2 and £4.74 with Orange.

Consumers spent approximately £500 million on directory enquiries calls in 2009. Ofcom found that low-income households were more vulnerable to high costs because they often don’t have landlines – 26% rely on mobiles for these kinds of calls, compared to just 9% of ABC1 households.

Clearly, mobile phone network operators and directory enquiries services need, at the very least, to be clearer with consumers about the charges they will incur. This could mean explaining the cost before connecting a caller to another number, for instance. At present, competition between firms doesn’t appear to have driven prices down in the way Ofcom anticipated. Some services are cheaper than others, however, and consumers should arm themselves with as much information as possible before making these calls.