A fixed term contract of employment is just as binding and enforceable as other contracts of employment. The terms are agreed between the parties and cannot be lawfully varied without further agreement.
If you wish to extend the contract beyond the expiry date you should discuss the matter with your employer, perhaps with the help of a trade union representative.
If you have had a series of fixed term contracts which have run back to back for four years since at least July 2002, then under the Fixed Term Regulations you may be entitled to a permanent contract of employment.
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