The good news is the rules aren’t that complicated. The bad news is the document that matters most is your contract, and most people haven’t read theirs since the day they signed it.
Here’s how UK notice periods actually work, in plain English.
Your contract is the document that matters
Open your employment contract. Find the section that mentions notice. That’s your notice period. It will say something like “one month” or “two weeks” or “three months”. For most office workers it’s one month. For senior roles it tends to be three months. For some hourly or casual work it might be a week or even less.
The notice period applies in both directions. You owe your employer that much warning if you’re leaving. They owe you that much warning if they’re letting you go (with the exception of dismissal for gross misconduct, where they don’t).
If your contract doesn’t mention notice at all, or if you don’t have a written contract, you fall back on the statutory minimum, which is a different thing entirely.
The statutory minimum is a backstop
The Employment Rights Act 1996 sets out the minimum notice that has to be given regardless of what (if anything) the contract says. It is not the same in both directions.
If you’re the employee, the statutory minimum you have to give is one week, once you’ve been employed for at least a month. Before a month of employment, technically no statutory notice applies on either side.
If you’re the employer, the statutory minimum you owe each employee is one week per full year of service, up to a maximum of twelve weeks. So someone who’s been with you four years is owed four weeks. Someone who’s been with you fifteen years is owed twelve weeks, because the cap kicks in at twelve.
Whichever is longer between the contract and the statutory minimum is what applies. In practice that’s almost always the contract, because contracts almost always specify longer than a week from the employee.
“One month” means a calendar month
This trips people up. “One month’s notice” doesn’t mean four weeks (which is twenty-eight days). It means a calendar month. Hand in your resignation on 15 March and your final working day is 15 April.
Where it gets fiddly is the end of the month. If you resign on 31 January with one month’s notice, there’s no 31st of February. The convention is to roll back to the last day of the relevant month, so 28 February in most years and 29 February in a leap year. The same rule handles 31 August + one month (which becomes 30 September) and any other month-end edge case.
For weeks the maths is simpler: two weeks means fourteen calendar days, not ten working days, and not ten weekdays. Calendar time, including weekends.
Yes, weekends and bank holidays count
Notice is measured in calendar time. A week is seven days. A month is a month. Bank holidays and weekends are just days like any others.
If your final working day lands on a Saturday, a Sunday or a bank holiday, most employers will treat the previous working day as your last day in the office. That’s a practical convention, not a legal rule. You’re still technically employed until the end of your notice period, you just don’t go in.
Probation, casual work, agency staff
The rules above assume you’re a proper employee with a contract for ongoing work. If you’re on a different arrangement, the rules can be different.
During probation, most contracts specify a shorter notice period, commonly one week. Some go further and require no notice in the first month. Read the probation clause of your contract before you assume.
On a zero-hours or casual contract, the arrangement can typically be ended without notice on either side, unless the contract specifies otherwise. There’s a difference between a “worker” and an “employee” in UK law, and most casual staff are workers. Workers don’t get the statutory minimum notice that employees do.
Agency workers are employed by the agency, not the end client. Your notice period is whatever your contract with the agency says, which is often very short or none at all. The end client can terminate the assignment without notice.
What if you don’t know your notice period
If you genuinely can’t find your contract or it’s silent on the subject, the answer is: probably one week, after you’ve been there at least a month. That’s the statutory minimum for an employee. Anything longer in writing trumps that.
A few things you can do to figure out what applies to you:
- Ask HR or your manager. There’s no penalty for asking, and they’d rather you ask than leave on the wrong terms.
- Check your offer letter. Notice is sometimes spelled out there even if it’s also in the contract.
- Check the employee handbook. Some employers put notice terms there rather than in the contract itself.
- Look on the staff intranet or wiki. For larger employers the standard contractual terms are often documented internally.
The bit nobody tells you
The legal notice period is the floor, not the ceiling. Plenty of resignations end up with a different actual exit date than the contract specifies. You and your employer can agree a shorter notice (very common). You can negotiate garden leave (you’re paid but stay home). You can be offered payment in lieu of notice, or PILON (employment ends immediately, you’re paid for the unworked notice). All of these are mutual arrangements that override the contractual default.
Your contractual notice gives you a baseline you can rely on. After that, what actually happens depends on what you and your employer agree.
So what should you do next
If you want to work out exactly when your last day falls based on your contract, the calculator on the home page does the arithmetic, including the month-end and bank-holiday edge cases. If you want to think about how to negotiate a shorter exit, the conversation usually starts with offering them something (a clean handover, a fixed end date in writing, availability for questions after you leave) and ends with them giving you something back (an earlier release date). See the companion guide for how that conversation actually goes.
This is general information, not legal advice. Your contract and your specific situation may change the answer. If something significant is at stake, take advice from ACAS or an employment-law solicitor.