If you are entitled in law to a redundancy payment (i.e. you have worked for your employer for 2 years or more and are being made redundant), you cannot be made to give up or 'sign away' that right, no matter what your contract says.
In particular, by virtue of the Fixed-term Worker (Prevention of Less Favourable Treatment) Regulations 2002, fixed-term workers who have been employed under a contract for 2 or more years cannot be made to give up their right to a redundancy payment, as used to regularly happen.
You can also download these two free publications with further advice:
Dealing with the Downturn TUC/Citizens Advice leaflet in Adobe pdf format.
Facing Redundancy Know Your Rights leaflet from the TUC in Adobe pdf format.
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