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Contracts of employment

Key points

  • A contract of employment is an agreement between an employer and employee and is the basis of the employment relationship.
  • Most employment contracts do not need to be in writing to be legally valid, but it is better if they are.
  • A contract 'starts' as soon as an offer of employment is accepted. Starting work proves that you accept the terms and conditions offered by the employer.
  • Most employees are legally entitled to a Written Statement of the main terms and conditions of employment within two calendar months of starting work. This should include details of things like payholidays and working hours. Download our word  Written Statement of Employment [53kb] template.
  • An existing contract of employment can be varied only with the agreement of both parties.

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

Some people might assume that a contract of employment consists of only those things that are set out in writing between an employer and an employee. It's true that many of the main issues, such as pay and holidays, are usually agreed in writing.

But contracts are also made up of terms that have not been spelt out. This is either because they are:

  • too obvious to mention: for example, you would not expect a contract to say that 'an employee will not steal from an employer'
  • necessary to make the contract work: for example, if you are employed as a driver it is assumed that you have a valid driving license
  • custom and practice: some terms of a contract can become established over time.

It is best to put a contract in writing - it saves a lot of potential misunderstanding further down the line. In Acas' experience simple misunderstandings over what is or what is not in a contract are one of the main causes of employment tribunal claims.

Acas services

The Acas Helpline can provide advice and guidance if you have specific employment relations issues. We also have helpful modules on the Acas Model Workplace, which are free to access and use. Acas can also provide advisory services (see Contracts and hours: how Acas can help), free eLearning and training courses on contracts of employment. If your organisation would benefit from more tailored business solutions, contact us through our online enquiry form.

Acas Productivity tool

Take the Acas self-diagnosis Productivity Tool test to understand your organisation's strengths and weaknesses, and to help you identify simple practical steps you can take to get the best out of your staff. The tool will produce a report with links to relevant Acas help and tools.

Acas Helpline

Call our Helpline on 0300 123 1100 for free support and advice or to check your workplace policies and practices. The Acas Helpline provides free and impartial advice for employers, employees and representatives on a range of employment relations, employment rights, HR and management issues.

Some feedback about our Helpline from users:

"Acas is invaluable. We have had lots of HR issues and nobody else to ask."

"Everything that I have asked Acas on the Helpline, they have informed us correctly and in full."

Helpline number: 0300 123 1100
Monday-Friday: 8am-8pm and Saturday 9am-1pm

View further information about our Helpline service, including our new Helpline Online on the Acas Helpline page.

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