CONSUMERS have been warned that using Skype, the software that offers cheap or free phone calls over the internet, could cost you more than traditional calls.

The news emerged as Three, the mobile phone operator, became the first to offer Skype on a traditional mobile handset, allowing you to make free calls to other users anywhere in the world.

Until now, most people have used Skype from their laptops, using a headset to make the calls. The software routes the calls over the internet – known as voice over internet protocol or Voip. If you are phoning another Skype user, anywhere in the world, it will cost you nothing.

A second service, Skype Out, offers cheap calls to nonusers – but research last week revealed that you could pay more than with traditional calls.

While Skype Out calls to landlines cost just 1.4p a minute, calls to mobiles cost 16.6p. Calling a mobile in the traditional way, from a landline, costs between 3.6p and 12.6p with BT.

Rob Barnes, mobile expert at comparison firm Moneysuper-market, said: “There is a lot of hype around Skype, and while some of it is justified, you could end up paying more in some circumstances.”

Three’s new mobile will offer Skype, but not Skype Out, and works out cheaper than making traditional calls.

The Skypephone, available from last Friday, is free for contract customers spending at least £12 a month. It will cost £49.99 for prepay users as long as they spend at least £10 a month on top-ups.

Calls made through Skype are free to other Skype users anywhere in the world, allowing customers to save hundreds of pounds a year, especially if they make calls abroad.

Vodafone, for example, charges 94p a minute to most EU countries and £1.29 a minute to call the US. You can reduce this by paying an additional £2.50 a month to subscribe to the international call saver option, cutting the cost to 25p a minute to the US and Europe.

The cheapest £12 a month deal comes with 100 free bundled minutes as well as 4,000 minutes of internet telephony calls a month, and 10,000 monthly Skype “chat” messages which are like texts. A £15 a month package offers 300 free bundled minutes a month.

When you are out of bundled minutes, and you are calling non Skype users, you are charged a flat rate of 12p a minute for calls to mobiles or landlines in Britain, and 30p to Europe and America This makes it one of the cheapest out of bundle deals. T-Mobile charges 20p a minute, Orange charges 35p and Vodafone 40p.

Though internet telephony is not new, this is the first time a mainstream UK operator has fully integrated the technology into one of its handsets.

About 2.5m people in Britain and 250m worldwide use Skype, owned by the auction website eBay. Until recently, however, it has only been possible to use Skype using a computer or a relatively upmarket smartphone.

Barnes said: “This is one of the cheapest and most cost-effective phone deals in the market at the moment. Even if you take the Skype element out, 3’s deal is pretty good.”

Rob Rawlinson, managing director at Mobileshop.com, said: “If 3 manages to persuade people that this is not just for computer-savvy people, it may force other operators to consider the technology.”

The major mobile operators in Britain have been reluctant to embrace Skype as it undermines the established network, which has cost billions of pounds to set up. In some cases, operators such as Vodafone have been accused of blocking customers downloading Voip software on to their handsets.

T-mobile is the only mainstream operator to offer Voip from one of its mobile handsets, but it costs customers at least £52.50 a month as you have to subscribe to a top end 18-month “web n walk max” tariff.

However, 3 has been working with Skype for over a year and already allows for Voip calls on its X-Series tariffs. This lets customers download Skype software on to their phones for an additional £5 a month.

The new phone, though, made by the Chinese handset manufacturer Amoi, is designed to appeal to a much wider audience by integrating Skype.

There are a number of other ways you can make Voip calls. Some mobile handsets such as the N95 from Nokia, for example, have an in-built Voip function. But unlike 3’s new handset, which uses the extensive 3G network, the N95 relies on the less widespread wi-fi network.

This works through “hot spots” dotted in cafés, airports and stations across the country. If you are outside these areas you won’t be able to make an internet call. You’ll also be cut off if you move away from a hotspot.

Other operators that use wi-fi to make calls include Truphone, Belkin and Mobiboo.

Even BT introduced a Voip phone in the form of its Fusion handset. This routes calls over the internet if you are close to a wi-fi signal.

Michael van Swaaij, acting chief executive at Skype, said: “Thanks to 3, Skype has now taken a giant step forward in the mobile arena. It takes an innovative operator like 3 to challenge traditional thinking and offer the kind of product other operators are still shying away from.”

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