Notice period calculator: the last day of employment
Dates, not money: when notice actually starts, and exactly which day the employment ends. For what notice costs, see the notice pay calculator.
The dates
Convention, not statute: notice runs from the day after it's given (per Acas; written notice from when there's been reasonable time to read it), and a month runs to the corresponding date in the later month. The contract can define the counting differently - if it does, the contract wins.
Notice starts the day after it's given, not the day it's given (Acas) - so one week's notice handed over on a Monday means the last day is the following Monday. A month's notice runs to the corresponding date in the next month: given on the 15th, it ends on the 15th. Given on the 31st into a shorter month, it ends on that month's last day.
How much notice does an employer have to give?
| Who's giving notice | Service | Minimum |
|---|---|---|
| Employer | 1 month - 2 years | 1 week |
| 2 - 12 years | 1 week per full year | |
| 12+ years | 12 weeks (the cap) | |
| Employee | 1 month + | 1 week (never rises) |
Most contracts set more than the statutory floor on both sides - a month is the common baseline for salaried roles, three months for senior ones. Whichever is longer, contract or statute, is what applies.
The three counting rules people get wrong
- Starting the count a day early. Notice runs from the day after it's given. Resign on the 1st with a week's notice and the last day is the 8th, not the 7th. Written notice starts once there's been reasonable time to read it - a letter left on a desk on Friday evening doesn't start the clock that day.
- Months are not 4 weeks. A month's notice uses the corresponding date - it's 28 to 31 days depending where in the year it lands. "One month or four weeks" written in a contract are two different last days.
- The 31st into a shorter month. No 31st in the next month means notice ends on that month's last day - it doesn't spill into the month after.
Ending earlier - or later
Employment can end before the notice runs out by agreement, or immediately via a PILON - the notice is paid as a lump sum instead of worked, which normally needs a contract clause; the notice pay calculator costs it. An employer can also put the person on garden leave for the notice period - employed, paid, at home, and the last day stays exactly where this calculator puts it. Statutory redundancy sits on top of notice, not inside it - the redundancy cost calculator stacks the full exit cost.
Frequently asked questions
When does a notice period start?
Per Acas, the notice period starts the day AFTER notice is given - the day after the employee resigns, or the day after the employer tells the employee in person. Notice given in writing starts once the employee has had a reasonable amount of time to read it. The contract can set its own counting rules, so always check it.
How is one month's notice counted?
The usual convention is the corresponding-date rule: a month's notice given on the 15th runs to the 15th of the next month. If there is no corresponding date - a month's notice given on 31 January - it runs to the last day of the shorter month. Contracts can define the counting differently, and that definition wins.
How much notice does an employer have to give in the UK?
From the employer: at least 1 week after a month's service, then 1 week per full year of service from 2 to 12 years, capped at 12 weeks. From the employee: at least 1 week after a month's service - the employee's statutory minimum never rises, though contracts usually require more.
Can the employment end before the notice period runs out?
Yes, in two main ways: by agreement, or through a payment in lieu of notice (PILON), where the employment ends immediately and the notice is paid as a lump sum - which normally needs a PILON clause in the contract.
This calculator applies the statutory rules as published and shows its working, but it cannot know your contracts, your policies or anything unusual about the case. Treat the figure as a starting point, and take advice on anything contested or expensive.
Notice dates that compute themselves
CoDash keeps start dates, notice periods and leaver checklists per person - so when someone resigns, the last day, the handover plan and the paperwork are one screen, not a diary argument.