Probation periods and the six-month rule: how to work out the dates before 1 January 2027

The short version

• Probation is your contract, not the law. The law does not set a probation length. The Employment Rights Act 1996 describes a probationary period as a temporary period in the contract, starting at the beginning of the employment, to let the employer assess suitability. If you have one, the written statement of particulars must say so. Passing it does not change when someone can claim: only continuous employment counts (section 108).
• Count from the start date. Continuous employment begins with the day the employee starts work (section 211).
• The end of the job is what is tested. Service is measured to the effective date of termination, which is later than the day you decide, because of notice. Even with no notice, the law treats it as at least a week later for someone with a month’s service (sections 97(2) and 86).
• A six-month probation can end too late. If probation ends on the six-month date, a decision at the end is taken when the person can already claim.
• A genuine reason and a fair process are what protect you. Not the date.

This guide is general information, not legal advice. It covers Great Britain, not Northern Ireland.

The dates, step by step

1. Start date. The day the person’s continuous employment began.
2. Six-month date. The same day of the month, six months later. If there is no such day (31 August plus six months), use the last day of that month.
3. Protected from (cautious). From 1 January 2027 section 108(1) will require “not less than six months” ending with the effective date of termination. The Act says a month is a calendar month and the start day counts (sections 210(2) and 211(1)(a)), but not how to count the end date. The Court of Session counted a year starting on 8 April as ending on 7 April (Pacitti Jones v O’Brien [2005] CSIH 56, a Scottish appeal decision, so persuasive rather than binding in England and Wales). So the cautious approach treats the six months as complete at the end of the day before the six-month date. Where the person qualifies sooner than 1 January 2027, use 1 January 2027, because the new rule applies to jobs ending on or after that date.
4. Last day to give notice. The protected-from date, minus one day, minus the notice period (at least 7 days for someone with a month’s service, and more if your contract requires). A notice given on that day ends the job the day before the protected-from date. “Given” means the day the employee receives the notice and has had a reasonable chance to read it, not the day you write or post it: hand it over and keep a record. The date may fall on a weekend or bank holiday, so plan to act on the working day before.
5. Suggested final review. Our own suggestion: 14 days before that, so there is time to write to the person and hold the meeting.

For anyone who started before 1 July 2026 the protected-from date is 1 January 2027, unless they already have two years. For a job that ends before 1 January 2027, the two-year rule still applies. If the end date is within a week or so of 1 January, take advice: the transitional rule turns on the effective date of termination, and how it interacts with the notice rule is a point to check.

Why a six-month probation can be too long

Many small employers set a six-month probation. For someone starting on 15 July 2026 it ends on 15 January 2027, a day after the cautious protected-from date of 14 January. A decision taken at the end of it is taken when the person can already claim. That is not a reason to rush a decision: it is a reason to hold the real reviews earlier, on the evidence, and to decide whether a shorter probation or an earlier final review suits your business. For people you hire from now on you can change the contract wording. Do not extend a probation unless your contract allows it, and if it does, confirm the extension in writing before the original probation ends and update the written statement of particulars within one month (Acas).

Running reviews fairly

• Write down what the job needs in a few clear objectives, and give them to the person on day one with the probation terms.
• Review at set dates (for example weeks 4, 8 and 12). Say what is going well, what is not, and what help you will give. Write it down and give a copy.
• Raise concerns promptly, with examples and dates. Do not save them for the end.
• Check for a protected reason. If a health condition or disability, pregnancy or another protected reason may be behind a problem, take advice. Those claims need no minimum service.
• If you are considering ending the employment, have a genuine reason (capability, conduct or some other substantial reason), and follow a fair procedure in line with the Acas Code, adapted to the case: tell the person in writing what the problem is and what it could lead to, hold a meeting without unreasonable delay, allow them to be accompanied at a formal meeting that could lead to a warning or dismissal, decide and tell them in writing, and offer an appeal. The decision-maker should have the authority to dismiss.
• Do not pick a date and then look for a reason. Fairness does not turn on the date; eligibility to claim does. Acas says that ending probation before protection starts “does not avoid legal risks”: discrimination, whistleblowing, pregnancy and wrongful dismissal claims do not depend on it.

Scotland and Wales

Employment law is reserved to the UK Parliament (Scotland Act 1998, Schedule 5, Part II, Head H), and section 25 extends to England, Scotland and Wales. The counting and the transitional rule are the same in Scotland. This guide does not cover Northern Ireland.

Sources

Last checked 28 October 2026.

• Employment Rights Act 2025, section 25 and S.I. 2026/559, legislation.gov.uk
• Employment Rights Act 1996: section 1, section 86, section 97, section 98, section 108, section 210 and section 211, legislation.gov.uk
• [Pacitti Jones v O’Brien [2005] CSIH 56](https://www.scotcourts.gov.uk/media/j0ym05jv/2005csih56-pacitti-jones-vclaire-obrien.pdf), Court of Session
• Scotland Act 1998, Schedule 5, legislation.gov.uk
• Acas Code of Practice on disciplinary and grievance procedures, Following a fair procedure, Probation periods, Extending a probation period and Employment Rights Act 2025: what is changing and when, Acas

Changes to this guide

• 28 October 2026: Published as a draft for review.

This guide is general information written from the official sources listed above and checked on 28 October 2026. It is not legal, tax or financial advice, and Plainfiles is not endorsed by any government body. Rules change, so check the linked official pages for your own situation. Written and designed by Plainfiles with the help of artificial intelligence (AI) tools, then checked against the official legislation and guidance listed in the sources. How we write and check our guides.