The Employer's Guide to Probation Periods: Setting Them Up Right
Probation periods give you a structured window to figure out if a new hire is actually going to work out. They're not required by law in the UK, but they're one of the few formal tools you have to assess performance before someone's been with you long enough to claim unfair dismissal. Used well, they're a safety net. Used poorly—or forgotten about entirely—they become a liability.
This employer's guide to setting up probation periods covers what you need to know: how to structure them, set clear expectations, conduct reviews, and make the final call.
What is a probation period?
A probation period is a defined stretch at the start of employment—typically three to six months—during which you assess whether the new employee meets the required standard. The key legal points are:
- Probation isn't required by law, but it's standard practice.
- During probation, shorter notice periods usually apply (often one week).
- The process for ending employment is simpler than it would be once probation ends.
- The employee still has rights: they cannot be dismissed for discriminatory reasons, and you must act fairly and reasonably.
ACAS guidance on hiring someone sets out the best-practice framework for UK employers, and the employee is entitled to a written statement of employment particulars that includes probation terms.
Why set probation periods?
Probation creates a formal framework for evaluating a new employee's performance, behaviour, and cultural fit. Without one, performance concerns often drift for months before anyone acts on them.
Most probation clauses include shorter notice requirements—typically one week—compared to the standard notice period after probation. This gives you flexibility if the arrangement isn't working, and it gives the employee clarity about what they're signing up for.
A well-managed probation period communicates exactly what the employee needs to demonstrate to succeed. This reduces ambiguity and gives them a fair chance to get up to speed.
While probation doesn't remove the need to act fairly, it does provide a recognised framework for ending employment early if the employee isn't meeting the required standard—provided you've documented the reasons and given feedback along the way.
Setting up probation effectively
Duration and contract
Three months is standard. Six months is common for more senior, complex, or safety-critical roles. Choose a duration that gives you enough time to assess someone without dragging it out indefinitely. (The point is evaluation, not psychological warfare.)
State the probation period in the employment contract—including the start date, duration, notice periods during and after probation, and what happens at the end. This is part of the written statement of employment particulars that employees are legally entitled to receive.
Clear objectives
At the start of probation, set clear, measurable objectives the employee needs to achieve:
- Specific: "Complete the product training programme" rather than "learn the role."
- Measurable: "Process 20 customer orders per day with less than 2% error rate" rather than "be good at the job."
- Achievable: Targets that a competent new hire could realistically meet within the timeframe.
- Time-bound: Aligned with probation milestones.
Write these down and keep copies. Link them to the job description they saw during hiring. Probation isn't about moving the goalposts; it's about confirming someone can actually do the job they applied for.
Support and feedback
Probation is not a test designed to trip people up. It's a period where the employee should receive enhanced support:
- Regular check-ins with their manager (at least fortnightly).
- Access to training, resources, and tools they need.
- A buddy or mentor for day-to-day questions.
- Clear, timely feedback on what's going well and what needs to improve.
If an employee fails probation despite receiving no feedback or support, you don't have a performance problem—you have a process problem.
During probation: regular check-ins and reviews
Schedule one-to-one meetings throughout probation to review progress against objectives, provide specific feedback, identify concerns early, and ask how they're finding the role. Document these conversations briefly—a few bullet points on what was discussed and any actions agreed. This creates a record that's invaluable if you later need to justify a probation decision.
Conduct a formal review at the midpoint of probation. This structured conversation should cover progress against objectives, strengths demonstrated, areas for improvement, any concerns from either side, and specific actions for the remainder. If there are performance concerns, the mid-probation review is your chance to give clear notice that improvement is needed and specific guidance on what "improvement" looks like. Without this, ending probation later for poor performance can feel unfair and is harder to defend.
If you spot performance or conduct issues, address them immediately. Don't wait until the end hoping things improve on their own. Early intervention gives the employee the best chance to succeed and demonstrates that you acted fairly. Document concerns and the support or guidance you provided—this paper trail is your evidence that the employee was given a fair opportunity. If you're managing time recording or attendance through a system, probation is a good time to confirm those processes are working for the new employee.
End of probation: three options
Confirm employment. The employee has met the required standard. Confirm their employment in writing, noting that probation has been successfully completed. If notice periods, salary, or other terms change after probation, confirm this too.
Extend probation. If the employee is making progress but hasn't fully met the standard, extend probation by a defined period (typically one to three months). Communicate the extension in writing with clear reasons, accompanied by specific objectives for the extension period. The employment contract should allow extensions; without this clause, extending unilaterally could be challenged.
End employment. If the employee hasn't met the required standard despite feedback and support, you may end employment. Even during probation, you should have documented evidence of the performance concerns, have given feedback and an opportunity to improve, conduct a final meeting to explain the decision, and provide contractual notice or payment in lieu.
While probation employees have fewer rights than permanent staff in some areas, they still have rights against discriminatory dismissal and other protected grounds. The ACAS Code of Practice on disciplinary and grievance procedures remains the benchmark for fairness. Always act fairly and reasonably—it costs nothing and protects you.
Common probation mistakes to avoid
No clear objectives. Starting without specific objectives means you have no objective basis for your decision. Set expectations on day one.
No feedback during probation. If the first time an employee hears about concerns is at the end-of-probation meeting, you've failed the process. Feedback should be ongoing.
Not documenting anything. Without written records of objectives, check-ins, and feedback, your decision is based on undocumented impressions. This is weak ground, especially for a negative decision.
Forgetting the review. If probation expires without a review and the employee keeps working, probation may be deemed complete by default. Set a calendar reminder four to six weeks before the probation end date.
Being too harsh or too lenient. Some managers use probation as a pressure tool, creating anxiety. Others pass everyone through regardless of performance. Neither serves the business or the employee.
Frequently asked questions
Can I have a probation period longer than six months? Technically yes, but courts are sceptical of probation periods longer than six months. The longer probation lasts, the harder it is to argue you're still assessing whether the person is a good fit. Stick to three to six months. If you need longer for a genuinely complex role, extend once rather than setting a long initial period.
What if I don't mention probation in the contract? You're not breaking the law, but you've lost the legal advantage probation gives you. Going forward, any new employee should have a formal probation period in their contract.
What if I've forgotten to review an employee's probation? If probation has expired without a formal review and the employee has kept working, it may be deemed complete by default. You can't then make a retroactive decision to fail them. Set reminders well in advance.
Do probation periods protect me against unfair dismissal claims? Partly. Probation employees are harder to claim unfair dismissal in their first two years, but they still have rights against discriminatory dismissal and dismissal for protected reasons (whistleblowing, jury service, etc.). Always follow fair procedures.
Can I change the objectives mid-probation? You can adjust them if circumstances change, but communicate this clearly in writing and give the employee time to respond. Don't ambush someone at the end-of-probation meeting with new criteria they were never told about.
What's the typical notice period during probation? One week is standard, but you can set any period by agreement. Whatever you choose, state it in the contract. After probation, the statutory minimum is one week (unless you've agreed something longer), as covered in our guide to UK statutory leave entitlements.
Do I need a formal meeting to end probation? Yes. Even if the decision is to confirm employment, a brief formal meeting or written confirmation is best practice. If the decision is to extend or end employment, hold a meeting to explain your reasoning, listen to their perspective, and confirm next steps. This demonstrates fairness and creates a paper trail.
Can an employee request flexible working during probation? Yes. Flexible working requests must be considered fairly whether someone's on probation or not, as covered in our guide to flexible working requests. However, ensure flexible arrangements don't prevent you from properly assessing their performance during the probation period.
The bottom line
Probation periods work best when they're structured, supportive, and well-documented. Set clear expectations at the start, provide regular feedback throughout, and make a considered decision at the end. Done right, probation is a tool that helps good employees succeed and gives both parties confidence in the working relationship.