Probation reviews at six months will be too late

From 1 January 2027 most employees can claim unfair dismissal after six months, not two years. Why a six-month probation review now arrives a week too late.

On 1 January 2027 the waiting period before most employees can claim unfair dismissal falls from two years to six months. The change is already law: the commencement regulations were made in May. For a small London employer the practical effect is narrow and easy to miss. A probation review set at six months now lands just after the protection starts.

What changes on 1 January

Today an employee needs two years' continuous service before they can bring an ordinary unfair dismissal claim. For any dismissal that takes effect on or after 1 January 2027, they need six months. The rule turns on the date the employment ends, not the date someone was hired, so service already built up counts. Anyone who joined you in the first half of 2026 will already be past six months when the new rule starts.

Two other changes travel with it. The cap on the compensatory award for unfair dismissal goes on the same day, so awards will rest on the losses the employee can show. And since 1 October 2026, staff have six months rather than three to take a claim to an employment tribunal.

Some things do not change. Protection against discrimination, and against dismissal for an automatically unfair reason such as whistleblowing, already applies from the first day. The gov.uk guidance on who can claim sets out both.

The week that catches people out

When an employer ends someone's employment, the law adds the statutory minimum notice to their service when it counts the qualifying period. After one month in the job, that minimum is one week. So a dismissal with a week's notice, or with pay in lieu of it, counts as if the employee had worked that extra week.

Put the two rules together and a probation review at the six-month mark is too late to be safe. If you are going to let someone go at the end of probation, the decision and the notice need to land at least a week before the six-month point. A review in the fifth month leaves room to act on it.

What it looks like for one small employer

Illustration, not a real client. A coffee roaster in Hackney Wick hires a warehouse assistant who starts on Monday 4 January 2027. The contract has a six-month probation and one week's notice during probation.

Six months' service is complete at the start of July 2027.
A review booked for the first week of July is a review held after the protection has arrived, once the week of statutory notice is added.
To keep the decision clear of that line, any notice has to be given by about 25 June, a week before the six months are up. Holding the review at the end of May or the start of June leaves time to act on it.

None of this stops the roaster dismissing someone after six months. It means a dismissal after that point needs a fair reason and a fair process, the same as for someone who has been there for years.

Why I would move the review, not the hiring

The obvious reaction is to hire less, and for most small firms it is the wrong one. When I started Zmartly I hired people who could do about 80 per cent of the job, and for years I did the other 20 per cent myself. The lesson I took was to hire people qualified for the role. The new rule adds a second one: find out in the first few months, and act on what you find.

That is mostly paperwork, and cheap paperwork at that:

Check your contracts. Probation periods, notice during probation and the review date should agree with each other.
Book a review at three months and a decision point at five. Put both in the diary on the day someone starts.
Write things down as they happen. A short note after each review, shared with the employee, is worth more than a long one written after a decision.
Cost the hire properly before you make it. Wages, employer National Insurance and pension come first; the time you spend managing someone who is not working out is the cost nobody budgets for. Our guide to the full cost of a first hire sets out the numbers for 2026/27.

Anyone you take on from now will reach six months after the new rule starts. Their probation reviews belong in the fifth month, and the contract template is worth fixing before the January hiring round starts.

About the author

Harvey Dhillon is the founder and CEO of Zmartly, a UK accountancy firm for small businesses. He grew up in West London and began his career in investment banking finance at Barclays, before going full-time on Zmartly in 2020. He is a Chartered Management Accountant (ACMA, CGMA).

Featured photo by Nellie Adamyan on Unsplash.