Zero-hours contracts are one of the most misunderstood employment arrangements in the UK. Used by roughly 1.1 million workers according to the Office for National Statistics, they are a genuine staffing tool for businesses that face unpredictable demand — think a seaside café in Norfolk, a care agency in Manchester, or an events company in Edinburgh. Done properly, they offer flexibility for both employer and worker. Done carelessly, they expose your business to costly Employment Tribunal claims. This guide sets out exactly what the law requires, what best practice looks like, and how to avoid the most common pitfalls.
What Is a Zero-Hours Contract?
A zero-hours contract is an arrangement where the employer makes no guarantee of any minimum working hours. You offer work when it is available; the worker can accept or decline. There is no obligation on either side to provide or accept a set number of hours each week.
Despite the name, a written contract is still strongly advisable — and legally required in certain respects. Under the Employment Rights Act 1996, all workers are entitled to a written statement of their main terms from day one of employment. This must include how pay is calculated, notice periods, and holiday entitlement. Failing to provide this written statement is itself a breach that can attract a Tribunal award of up to four weeks' pay.
It is also worth being clear about employment status. Zero-hours workers are usually classified as workers (not employees), which means they have a defined set of rights — but fewer than a full employee. They are not classified as self-employed contractors, a distinction HMRC takes seriously when it comes to National Insurance contributions and tax liability.
Legal Rights Zero-Hours Workers Are Entitled To
Just because hours are not guaranteed does not mean rights disappear. Zero-hours workers in the UK are entitled to a meaningful package of protections, and business owners must account for all of them.
- National Minimum Wage (NMW) / National Living Wage (NLW): Every hour worked must be paid at at least the current NMW or NLW rate. From April 2025, the NLW for workers aged 21 and over is £12.21 per hour. There are no exceptions for zero-hours arrangements.
- Statutory holiday pay: Zero-hours workers accrue 5.6 weeks of paid annual leave per year, calculated on a pro-rata basis relative to the hours actually worked. Since April 2024, irregular-hours workers accrue holiday at 12.07% of hours worked in each pay period — a change introduced to simplify calculations following the Supreme Court's landmark Harpur Trust v Brazel ruling.
- Rest breaks and working time limits: The Working Time Regulations 1998 apply in full. Workers are entitled to 20 minutes' rest during a shift of more than six hours, and a maximum average of 48 hours per week (unless they opt out in writing).
- Protection from discrimination: The Equality Act 2010 covers zero-hours workers. Treating someone less favourably because of a protected characteristic — age, disability, pregnancy, race, sex, and others — is unlawful regardless of contract type.
- Auto-enrolment pension contributions: If a zero-hours worker earns more than £10,000 in a tax year and is aged between 22 and State Pension age, you must auto-enrol them into a qualifying pension scheme. Even those earning below that threshold have the right to opt in.
Keeping accurate, up-to-date records of every hour worked is not optional — it is essential. If a worker disputes their holiday pay or claims they were underpaid, the burden falls on you as the employer to demonstrate otherwise.
The Exclusivity Ban and What It Means for Your Business
Since May 2015, exclusivity clauses in zero-hours contracts have been unenforceable. You cannot legally prevent a zero-hours worker from taking work with another employer. Attempting to do so, or penalising a worker for working elsewhere, gives them the right to bring a claim at an Employment Tribunal — and there is no minimum service period required to bring such a claim.
In practice, this means you should plan your workforce with the understanding that your zero-hours staff may well be working for a competitor on the days or weeks you do not offer them shifts. Build enough flexibility into your scheduling to accommodate this reality, and never put pressure — formal or informal — on workers to make themselves exclusively available to you.
The Employment Rights Bill: Changes on the Horizon
The Labour government's Employment Rights Bill, introduced in October 2024, proposes significant changes that will directly affect how zero-hours contracts work in practice. Business owners should start preparing now rather than scrambling to comply at the last minute.
The key proposed changes include:
- Right to a guaranteed hours contract: Workers who regularly work a consistent pattern over a reference period (expected to be 12 weeks) will have the right to request a contract that reflects their actual hours. Employers will be required to offer this — though workers will retain the right to decline and remain on a zero-hours arrangement if they prefer the flexibility.
- Reasonable notice of shifts: Workers will be entitled to reasonable advance notice of their working schedule, and to compensation if shifts are cancelled or curtailed at short notice.
- Protection against unfair shift cancellation: Where a shift is cancelled without reasonable notice, the worker will be entitled to a payment reflecting the lost earnings.
The precise timelines and definitions (such as what constitutes "reasonable" notice) are still being consulted on, but many of these provisions are expected to come into force from 2026. If you currently rely heavily on zero-hours staff — particularly in hospitality, social care, or retail — now is the time to review your scheduling practices and consider how you will evidence shift offers and cancellations.
Best Practices for Managing Zero-Hours Workers Fairly
Legal compliance is the floor, not the ceiling. Businesses that treat zero-hours workers well tend to retain better staff, reduce no-show rates, and avoid the reputational damage that comes with Employment Tribunal proceedings. Here is what good looks like in practice.
- Use a clear written contract: State the nature of the arrangement honestly, set out how pay and holiday are calculated, and confirm the worker's right to work elsewhere. Ambiguity breeds disputes.
- Track hours meticulously: Use a system that records actual hours worked against each worker, not just shifts offered. This is particularly important for holiday pay calculations. BizHub365's payroll module can help here — it handles RTI submissions to HMRC and supports irregular-hours workers, so you are always paying the right amount at the right time.
- Give as much notice as possible: Even before the Employment Rights Bill becomes law, giving workers advance notice of their shifts is simply good management. It reduces last-minute drop-outs and builds trust.
- Review patterns regularly: If a worker has effectively been working the same hours every week for six months, they may have acquired employment rights beyond basic worker status. An employment law solicitor or a professional body such as ACAS can help you assess the position.
- Keep communication professional and documented: Send shift offers in writing (even by text or email), and keep a record. If a dispute ever arises, a clear paper trail is invaluable.
Conclusion: Flexibility and Fairness Are Not Mutually Exclusive
Zero-hours contracts are a legitimate and useful tool for UK small businesses — but they are not a loophole to sidestep employment law. Workers on these contracts have real rights, and the regulatory direction of travel under the Employment Rights Bill is firmly towards greater protection and predictability for them.
The businesses that will navigate these changes most successfully are those that already treat their zero-hours workers with transparency and respect: clear contracts, accurate pay, proper holiday accrual, and honest communication about shift availability. Get your processes in order now — and if managing payroll and compliance for an irregular workforce feels overwhelming, tools like BizHub365 can take much of the administrative weight off your shoulders, leaving you to focus on running your business.