Can an employee claim unfair dismissal on expiry of a fixed-term contract of employment?

Yes, the expiry of a fixed-term contract is classed as a dismissal in law, meaning that the employee could claim unfair dismissal, provided that they have the required service. This includes the case where a contract terminates on the completion of a specific task. 

The qualifying service required to claim unfair dismissal reduces from two years to six months for dismissals on or after 1 January 2027. 

To defend an unfair dismissal claim, the employer would have to show that it had a fair reason for dismissing the employee (for example redundancy or "some other substantial reason") and that it acted fairly and reasonably in dismissing the employee for that reason.