There is no formal legal definition of "residence". The Inland Revenue's practice - based on a mixture of statute and court decisions -  is to regard you as resident in the UK during a tax year if :

· You spend 183 days or more in the UK during the tax year, or

· Although here for less than 183 days, you have spent more than 90 days per year in the country over the past four years (taken as an average). You will then be classed as UK resident from the fifth year.

There is also no statutory test of ordinary residence. You will be classified as a UK ordinary resident if the UK is your "normal place of residence".

On leaving the country you will continue to be regarded as UK ordinary resident unless you go abroad with the intention of taking up permanent residence overseas. This also applies for individuals returning to the UK.

The Inland Revenue normally interprets "permanent" to mean 3 years or more.