Sometimes an employee may resign in the heat of the moment. It could be an official resignation, or an act that implies resignation, such as clearing their desk, saying they will never return, etc. In such situations they might not really have meant to resign but did so on impulse. Therefore, the employer should not automatically assume that the employee has resigned and should allow a short cooling off period for them to change their mind if necessary.
The leading cases are those of Kwik-Fit Ltd v Lineham and Ali v Birmingham City Council. It was decided that an appropriate period for the employee to change his mind was "likely to be a day or two". That is on the assumption that the employee had not already been given the opportunity to reflect on their apparent resignation and retract it.
Therefore, in circumstances where an apparent resignation has occurred in the heat of the moment, the employer would be expected to give the employee a couple of days before treating their actions as a formal resignation. That time should be used by the employer to contact the employee in order to clarify their position. Failure to do so and take their resignation at face value could be treated as a dismissal instead, which could easily be challenged as being unfair in the employment tribunal.
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