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Changing or varying a contract

At some point, either party bound by a contract of employment may want to change it.

For example:

  • an employer may want to reorganise the business due to economic circumstances. This might mean changing working hours or pay
  • an employee may seek improvements in their pay or holidays, or want to change the hours they work due to domestic responsibilities.

An existing contract of employment can be varied only with the agreement of both parties. Changes can be agreed by with either on an individual basis or through a collective agreement. When any change to a contract of employment occurs the employer should give written notification of the changes in writing, within one month of the change taking effect.

There are some important steps you must take if you wish to try and change a contract - especially around consulting with employees. These are set out in the Advice leaflet - Varying a contract of employment.

Watch our expert adviser talk about one of the most asked questions to the Acas Helpline.