Free UK HR calculator

Probation period calculator

Work out when probation ends, when each review is due and the notice that applies at each point, from the start date and the contract's terms.

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Reviews, extensions and notice

Use the calculator

Work out the probation dates

Enter the start date and the probation length from the contract, choose the review points and add the notice during probation if the contract states one.

Tuesday 31 August 2027last day of probation (184 days)

Mid-point reviewTuesday 1 June 2027Notice if given that day: 1 week (contract and statutory minimum agree)
Final reviewTuesday 17 August 2027Notice if given that day: 1 week (contract and statutory minimum agree)
Probation endsTuesday 31 August 2027Notice if given that day: 1 week (contract and statutory minimum agree)

The working

6 months from Monday 1 March 2027 runs to Tuesday 31 August 2027, the day before the 6-month anniversary (184 days)
Mid-point review: 92 days in, on Tuesday 1 June 2027
Final review 2 weeks before the end: Tuesday 17 August 2027
Statutory minimum notice: none before one month's service, then 1 week from Thursday 1 April 2027
Contract says 1 week. Notice is the longer of the contract and the statutory minimum: 1 week on the last day of probation
Notice given on the last day of probation would end employment on Tuesday 7 September 2027. That is also the date that counts for unfair dismissal if employment ends that day with pay in lieu, as statutory notice is added
For that date the usual unfair-dismissal qualifying period in Great Britain is six months, and six months' service is complete on Tuesday 31 August 2027

Worth knowing

Probation isn't set by law. These dates come from the contract terms you entered. In Great Britain, the written statement must give the length and conditions of any probation from day one.
If you might extend, decide and confirm it in writing by Tuesday 31 August 2027, the last day of probation. Leaving it until after the end could be a breach of contract.
Ending employment at the end of probation would still count as after six months' service: statutory notice is added to the termination date for this test, even with pay in lieu. From 1 January 2027, most employees in Great Britain can then claim unfair dismissal, probation or not. A summary dismissal for gross misconduct is not extended this way, and needs advice.
Day-one rights apply throughout probation, including the minimum wage, paid holiday, protection from discrimination and from detriment for whistleblowing. A dismissal for many automatically unfair reasons, such as pregnancy or whistleblowing, needs no qualifying service.
In Northern Ireland the usual qualifying period for unfair dismissal is one year, and the 2027 change does not apply.
Whether notice must be given, or must run out, within probation depends on the contract wording. Read the clause before planning the final review.

Basis: Probation dates from the contract terms entered. Notice during probation is the longer of the contract and the statutory minimum: none before one month's service, then 1 week until two years' service. The unfair-dismissal dates are information only: check the facts and take advice before a decision. Rules checked 8 November 2026.

Acas probation periods Acas extending probation GOV.UK written statement Employment Rights Act 1996, section 86 Employment Rights Act 1996, section 97 GOV.UK unfair dismissal eligibility Commencement regulations 2026

The method

How the probation dates are worked out

There is no statutory probation, so the calculator starts from the contract. The law then sets the minimum notice at each point.

1
Count from the start date
A six-month probation runs to the day before the six-month anniversary. A probation in weeks counts seven days a week, start day included. An extension starts the day after the original end.
2
Set the review points
The mid-point sits half way through and monthly reviews fall on each monthly anniversary. The final review sits the chosen number of weeks before the end. A review that lands at a weekend moves back to the Friday, or on to the Monday if the Friday comes before an extension starts.
3
Check the notice at each point
Before one month's service there is no statutory minimum notice. After that it is one week until two years' service, or the contract's notice if that is longer.

Worked example

Worked example: a six-month probation from March 2027

A new starter joins on Monday 1 March 2027. The contract sets a six-month probation with one week's notice, a mid-point review and a final review two weeks before the end.

Inputs

Start date: 1 March 2027
Probation: 6 months
Mid-point review, and a final review 2 weeks before the end
Notice during probation: 1 week

Working

6 months from Monday 1 March 2027 runs to Tuesday 31 August 2027, the day before the 6-month anniversary (184 days)
Mid-point review: 92 days in, on Tuesday 1 June 2027
Final review 2 weeks before the end: Tuesday 17 August 2027
Statutory minimum notice: none before one month's service, then 1 week from Thursday 1 April 2027
Contract says 1 week. Notice is the longer of the contract and the statutory minimum: 1 week on the last day of probation
Notice given on the last day of probation would end employment on Tuesday 7 September 2027. That is also the date that counts for unfair dismissal if employment ends that day with pay in lieu, as statutory notice is added
For that date the usual unfair-dismissal qualifying period in Great Britain is six months, and six months' service is complete on Tuesday 31 August 2027

Probation ends on 31 August 2027, with the mid-point review on 1 June 2027 and the final review on 17 August 2027. Notice given on the last day would end employment on 7 September 2027, after six months' service.

Use it with context

Plan the dates, then make the decision with care

Use the dates to plan reviews and check the contract. They do not decide whether someone passes probation or whether ending employment would be fair.

This calculator covers

Probation in months or weeks, up to 24 months
One extension, running from the day after the original end
Mid-point, monthly and final review dates
Notice at each review from the contract and the statutory minimum

Check the full guidance for

Whether the contract or policy allows an extension
Bank holidays and the employee's own working days
Fair reason, fair process and automatically unfair reasons
Notice pay, payment in lieu and final pay

From calculation to record

Keep the probation end date with the person

HollyHR holds each person's start date and probation end date on their employment record, and the people directory marks who is still in probation.

See people records in HollyHR

Questions

About the probation period calculator

Is probation a legal requirement in the UK?

No. There is no legal requirement to have a probation period, and it can be any length. If you use one in Great Britain, the written statement must give its length and conditions from the first day of employment.

When does a probation period end?

On the date the contract sets. Where it gives a length, a three-month probation from 10 March runs to 9 June, the day before the three-month anniversary. Some contracts name an end date or count it differently, so read the clause.

Can you extend a probation period?

Only where the contract or probation policy allows it. Confirm the extension in writing before the original period ends and update the written statement within one month. Explain why, how long it will last and what support the employee will get.

What notice applies during probation?

The contract's notice if it states one, but never less than the statutory minimum. There is no statutory minimum before one month's service. After one month it is one week, both for the employer and for an employee who resigns. The employer's minimum then rises by a week for each complete year from two years' service.

Does probation change unfair-dismissal rights?

No. They depend on continuous service, not on probation. In Great Britain the usual qualifying period is two years where the effective date of termination falls before 1 January 2027, and six months where it falls on or after that date. Statutory notice counts towards that date even with pay in lieu. In Northern Ireland it is usually one year.

Why does a six-month probation need care from 2027?

Ending a six-month probation on its last day still counts as after six months' service, because statutory notice is added to the termination date for this test, even with pay in lieu. So the employee can usually claim unfair dismissal. A summary dismissal for gross misconduct is not extended this way, and needs advice.

Which rights apply from day one?

Day-one rights apply throughout probation, including the minimum wage, paid holiday, protection from discrimination and from detriment for whistleblowing. A dismissal for many automatically unfair reasons, such as pregnancy or whistleblowing, needs no qualifying service.

Keep going

Useful next steps

GuideOnboarding checklist

TemplateProbation review template

GlossaryProbation period

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