Introduction to this document

Extension of probationary period letter

Where a probationary employee is not achieving the standards of performance or conduct that you expect, you might wish to consider extending their probationary period. In this case, you will first need to check the position on extension under the employee’s contract of employment.

Probationary periods

When taking on new employees you might provide for a “probationary period” in order to enable you to assess their suitability for the employment. This is usually three to six months, although it could be longer or shorter. However, note that, in employment law terms, the labelling of an employee as a “probationer” has very little effect on the employer/employee relationship. Employees who have short service do not have the general right to claim unfair dismissal, although note that there are a number of exceptions to this rule. An employee can generally make a claim for unfair dismissal if they have been employed for two years or more. Therefore, the reality is that employees who are placed on probation will not be able to claim unfair dismissal if they are dismissed during or at the end of their probationary period.


You might feel that an employee is not quite performing or behaving to the high standards you expect. Therefore, you would like to extend the probationary period to serve as a “warning” that an improvement in performance and/or conduct is needed if they want to avoid being dismissed. Use our Extension of Probationary Period Letter here. The extension letter spells out that you will give the employee a further chance to improve during the extended probationary period but that, if the employee fails to do so, the next step is likely to be dismissal.


You should carefully investigate the reason for the employee’s lack of capability in their job. If the cause of poor performance is, for example, ill-health, lack of training or support, inadequate communication, problematic working relationships, faulty equipment or anything else that might be outside the employee’s control, you should take steps to address the problem.

Contractual position

In addition, before extending probation, check the employee’s offer letter or contract of employment to ensure it contains a right for you to extend it. This is particularly important if the employee does not have the benefit of certain contractual provisions during probation. If you extend probation without a contractual right to do so and thereby deny the employee valuable benefits for a further period of employment, your employee will have a potential claim against you for breach of contract. Your employee can only claim breach of contract before an employment tribunal if they are no longer employed (otherwise they have to go through the civil courts).