Part-time working
As a part-time worker and UNISON member, you are protected from being treated less favourably than equivalent full-time workers.
A part-time worker is someone who works fewer hours than a full-time worker or employee in the same organisation. There is no specific number of hours that makes someone full or part-time, but a full-time worker will usually work 35 hours or more a week.
Every employee has the right to request part-time hours, or other flexible working arrangements, from the first day of their employment. This request must be made in writing and the employer then has a two-month decision period within which to consider the request.
On this page
What is a part-time worker?
A part-time worker is defined as a person who is paid fully or in part by reference to the time they work, and are not identifiable as a full-time worker.
A full-time worker usually works at least 35 hours a week in the UK. The rights of part-time workers are legally protected by the Part-time Workers (Prevention of Less Favourable Treatment) Regulations 2000.
There are Northern Ireland equivalents to the regulations – The Part-time Workers (Prevention of Less Favourable Treatment) Regulations (Northern Ireland) 2000. Members in Northern Ireland have the same right to be treated equally to comparable full-time workers who work for the same employer and do similar work under the same type of employment contract.
Different types of part-time working
Term-time working and job sharing are both forms of part-time working. Members who work under such arrangements have the same rights as other part-time workers.
Pay rates for part-time workers
Legally, your employer must provide equal pay for equal work. The hourly rate for part-time and full-time workers doing the same work should be the same.
However, you may not be entitled to the same overtime rate as a full-time worker until you have worked the same number of hours that the full-time worker would be required to work before getting the overtime rate.
For example, where a full-time worker normally works 40 hours a week and is entitled to overtime rates for additional hours, a part-time worker who normally works only 20 hours a week would also have to exceed a 40-hour week to be entitled to enhanced overtime rates.
Your organisation might have a different policy about overtime, so you should check your contract.
What rights do part-time workers have?
A part-time worker must not be treated less favourably in relation to the terms of their contract or by being subjected to any other detriment by their employer. This includes any act or deliberate failure to act. The rights of part-time workers must be proved in comparison with actual (rather than hypothetical) full-time workers and complaints about any less favourable treatment must be on the ground that the worker was a part-time worker.
Part-time workers have the right to all the benefits and the protection that full-time workers get in an equal proportion to the number of hours that they work, unless the difference in treatment can be justified on objective grounds.
If you work part-time, you should receive the pro rata equivalent to a full-time worker for:
- pay and leave – including for holiday, sickness absence, maternity, paternity, adoption and shared parental leave;
- training and career development;
- opportunities for promotion, career breaks and job transfers;
- pension schemes;
- redundancy selection and pay.
Can you change from full-time to part-time working?
You can ask your employer to let you switch to working part-time. This request must be made in writing and your employer has two months to consider it.
Your employer can refuse your application for one (or more) of the eight reasons set out in the legislation (see our flexible working page), but they must explain why they have refused it.
Can your employer change your hours from part-time to full-time?
No, your employer cannot change your hours without you agreeing to the change.
Tax for part-time workers
If you work part-time and earn over a certain amount, your employer will deduct tax and national insurance contributions from your salary in the same way as if you were working full-time.
If you work part-time for more than one employer, you will get a special tax code for your second job to ensure you are taxed at the correct rate.
External advice and support
Frequently asked questions
Since 1 April 2024, some part-time workers (defined as ‘irregular hours workers’ and ‘part-year workers’) accrue statutory paid annual leave at the rate of 12.07% of hours worked. However, most workers have a right to a statutory minimum of 5.6 weeks’ paid annual leave and contractual paid annual leave often exceeds the statutory minimum amount that applies.
Legal disclaimer
The information contained within this article is not a complete or final statement of the law and is based on the laws of England, Wales, Scotland and Northern Ireland.
While UNISON has sought to ensure that the information is accurate and up to date, it is not responsible and will not be held liable for any inaccuracies and their consequences, including any loss arising from relying on this information. If you are a UNISON member with a legal problem, please contact your branch or region as soon as possible for advice, or for non-employment matters call UNISONdirect.