Microsoft has revealed how much users in the United Kingdom will have to stump up for its next operating system, Windows 7.

Windows 7 Home Premium Edition will cost £149.99, while the Professional version will be £219.99 and the Ultimate Edition £229.99.

The Home Edition is £20 cheaper than the equivalent version of Windows Vista. The Professional and Ultimate versions cost the same as their Vista equivalents.

Windows 7 will go on sale in the UK, the US and other territories on 22 October. However, unlike previous versions of Windows, there will be no upgrade price option for EU users.

Instead, all EU customers will have to pay for a brand-new licence, regardless of whether they are an existing Windows user. This situation is a result, says Microsoft, of it having to produce an 'e' version of its OS that doesn't come with the Internet Explorer browser preinstalled.

From the 22 October launch until "at least Dec 31st" Windows 7 Home Premium will be offered at the reduced price of £79.99 in all EU territories, said Microsoft UK spokesman John Curran.

Microsoft was sued in the EU for anti-competitive practice because it assumed customers would want to use its Internet Explorer browser and preinstalled it on Windows XP. However, the web browser is not an integral part of Windows and Microsoft was judged to have been anti-competitive to other browser makers in preinstalling IE on Windows PCs. Windows operating systems in the EU are therefore not allowed to ship with IE preinstalled.

In the US, Windows 7 will cost $119.99 for the Home Premium Upgrade version or $199.99 for the full version.

To sweeten the blow for EU customers penalised for not being able to get a cut-price upgrade version to Windows 7, Microsoft is instead offering Windows 7 Home Premium Edition for £79.99 if bought between the launch on 22 October and 31 December. The deal will apply to all EU territories.

Other special offers were also confirmed in a briefing with Microsoft. These include the launch on Friday of the Windows 7 Upgrade Option Programme and a pre-order scheme whereby customers can get hold of a full version of Windows 7 Home Premium or Windows 7 Business for £49.99.

Orders for Windows 7 at the special pre-order price will be limited to 25 per customer or per business. Microsoft describes the £49.99 deal as both "time-limited" and "quantity-limited". Indeed, a table details the different retail options for Windows 7 and indicated that Microsoft expects the £49.99 deal to end around 14 August.