Part-Time Workers

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Peninsula Group, HR and Health & Safety Experts

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In this guide, we’ll look at what a part-time worker is, what their legal rights are, and ensuring equal treatment of them and full-time workers.

Part-time working is a very common method many businesses use. They might use this type of employment for job sharing, creating full rotas, and even to provide a better work-life balance.

If you deny part-timers their legal rights or treat them less favourably, you could face serious consequences. Like, employment tribunal hearings, unlawful discrimination claims, and even reputational damage.

In this guide, we’ll look at what a part-time worker is, what their legal rights are, and ensuring equal treatment of them and full-time workers.

What is a part-time worker?

A part-time worker is a person who works fewer hours in comparison to a full-time worker. There are many reasons why people choose to be part-timers, like:

  • Better work-life balance: For example, if they want to concentrate on raising their family.
  • Carer’s responsibility: For example, if they’ve recently become the primary carer of their elderly parents.
  • Studying and education: For example, if they are studying at University and need more time to do so.

What is the law on part-time working?

If a person works part-time, they’re legally protected from receiving less favourable treatment compared to full-time employees.

You can’t treat someone less favourably simply because they don’t work full-time hours. This legal right stands for part-timers in the same role - doing the same or similar work - as comparable full-time workers.

The right to equal treatment is covered under a number of employment laws, like:

The right to equal treatment applies to both a part-time employee and worker. They also cannot be treated less favourably based on the type of employment contract they have (like a permanent or fixed-term contract.

What happens if a part-time worker is treated less favourably compared to a full-time worker?

If a part-time worker believes they were treated less favourably than full-time workers, they’re legally allowed to raise this claim to an employment tribunal (ET). They don’t need to have worked a minimum number of years to qualify for this legal right.

A part-time worker needs to prove they received less favourable treatment against a comparable full-time worker. Comparable full-time workers must:

  • Work for the same employer.
  • Work under the same type of employment contract.
  • Do the same type of work (or similar) and have the same hourly rate.
  • Work or be based in the same workplace. (Or, in a relevant working environment owned by the same employer).

People are often treated less favourably when they transition from being a full-time employee to a part-time one. For example, if their previous full-time contract allows maternity leave, then their recent contract should.

Can unequal treatment ever be objectively justified?

Yes, there are times where you treat someone unequally due to objective justification (OJ). Objective justification is when a person is discriminated against because their employer has a proportionate means of achieving a legitimate aim.

For example, if an employer provides health insurance, they wouldn’t have fair objective grounds to deny this request from a part-time worker.

Some people aren’t fully entitled to the right to equal treatment. For example, it may vary for self-employed people and job applicants.

How to ensure part-time workers are treated equally

All employers have a legal duty to treat their part-timers fairly - compared to their equivalent full-time workers.

This ranges from providing maternity leave rights to career development opportunities. With the right steps, you’ll be able to promote a workplace that champions equality, diversity, and inclusion.

There are many areas where you must treat part-time workers equally. For example:

Equal pay

A part-time worker has the same right to equal pay as a full-time worker who is doing comparable work. This should be on a pro-rata basis; meaning, it should be in proportion to how many hours worked and paid in the same way. This covers national minimum wage (NMW), bonuses, and performance-related pay (PRP).

They should be paid the same hourly pay rate as workers on full-time hours. For example, a full-time worker is paid an annual bonus of £500. A part-time worker who works half the number of hours should be paid £250.

Statutory sick pay

As individuals can qualify for statutory sick pay (SSP) providing they earn above the lower earnings limit of £118 per week. SSP payments will also be pro-rata - so employees who work three days a week will receive 60% of the full SSP payment.

However, you need to remember that staff will need to be incapable of work due to illness for at least four consecutive working days, not counting weekends or days they don’t normally work, therefore this may prevent part-time staff from qualifying for SSP in many instances.


A part-time worker has the same rights to join a pension scheme that’s provided to a full-time worker. This is worked out on a pro-rata basis that reflects their normal hours.

Overtime pay

A part-time worker has the same rights to overtime pay against a comparable full-time worker. Your employer can set the same hours threshold for overtime pay as they do for full-timers. So, you might have to work more hours than a full-time worker to receive overtime pay.

If they exceed the limit for normal full-time hours, they should receive the same enhanced overtime pay for working more hours than usual (but this depends on their employment contract).

Annual leave

A part-time worker is entitled to the same holidays as a full-time worker. Again, this is worked out on a pro-rata basis according to the number of hours they’ve worked.

If full-time workers who work five days a week can claim six weeks’ holiday each year (with pay), a part-time worker who works two days a week would receive six weeks’ holiday each year (with pay). But a “week” consists of only two days. Their pro-rata share is two-fifths of the full-time amount, which is 12 days.

Public holidays

A part-time worker should receive the same rights as a full-time worker when it comes to public holidays. If full-time colleagues receive time off for bank holidays, their part-time colleagues should also be given them on a pro-rata basis. Employers may offer them as an additional holiday or deducted from their annual leave entitlements.

If a part-time worker works on set days, employers should offer time off for bank holidays outside of their schedules. For example, if they usually work on Mondays (where most public holidays fall), you should give them paid leave on another day to cover bank holidays entitlements.

Training and career development

A part-time worker should be provided with the same work training and career development opportunities as a full-time worker.

This includes things like promotions, career breaks, and work experience. The only time employers can be selective is if their actions are objectively justified.

Maternity, paternity, and adoption leave and pay

A part-time worker has the same rights for family leave and pay as a full-time worker. This includes maternity, paternity, and adoption leave - and any payments that come with these entitlements.

Again, this is calculated on a pro-rata basis that reflects on their working hours, as well as other full-time workers.

Other legal rights

There are other basic legal rights that a part-time worker is entitled to. For example:

  • The right to work in a safe and healthy working environment.
  • The right to be accompanied by a trade union representative during grievance or disciplinary procedures.
  • The right not to be discriminated against because of a protected characteristic.
  • The right not to be victimised for enforcing their statutory rights.he right to a written statement of main terms and conditions of employment.

Part-time employees are also legally entitled to:

Get expert advice on part-time workers with Peninsula

All employers must ensure they treat part-timers fairly and equally. If they’re denied these rights or receive less favourable treatment, you could face serious consequences. Like tribunal hearings and compensation penalties.

Peninsula offers professional advice on part-time workers. Our teams offer 24/7 HR advice which is available 365 days a year. We take care of everything when you work with our HR experts.

Want more advice? Contact us on 0800 029 4377 and book a free consultation with an employment lawyer today.




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