I am being transferred back to the UK and will switch from a Swiss to a new UK contract at 1.3. However, my bonus, which relates to my performance during 2007 , is not payable until March - so I will receive income in Switzerland after I have officially started work in the UK. Will this be subject to UK tax as well as Swiss ?
Because of this my pension fund is also being kept open an extra month ( so the compulsory employer / employee contributions from my bonus can be paid in ) before being released to me. Does this have negative implications from a UK tax perspective ?

Thanks in advance for your advice.

At the outset, it has to be stated that your question cannot be finally answered based on your information.

As a principle, the bonus is subject to taxation in Switzerland, irrespectively you are at the time of the payment of the bonus already tax resident in the UK, as the bonus relates to your employment in Switzerland,

However, there may be a risk that the bonus is taxed in the UK as well according to UK tax law (which I don't know).

However, according to the Double Taxation Treaty concluded between Switzerland and the UK, the bonus should only be subject to taxation in Switzerland.