Calculating time in an employment relationship

The familiar units of time – days, weeks, months and even years – are not always easy to translate into a context where legal precision is required. The dispute between the Department of Health and the Royal College of Nursing about when its mandate for industrial action expired provides a recent example.

In that case the issue was about calculating the end of the period of six months “beginning with the date of the ballot”. The ballot closed at noon on 2 November 2022, so when did the authority of the ballot expire? The RCN had called a strike over the early May bank holiday, ending on 2 May 2023. The Government argued that the mandate ended on the previous day. When the RCN refused to back down, the Government obtained a court order declaring that the period of six months ended at midnight on 1 May. 

The judgment has not been published at the time of writing, but it is assumed that the reasoning focused on the meaning of the phrase “beginning with the date of the ballot”, which marks the start of the six month period. The legislation helpfully explains that where the ballot is open for a number of days, the date of the ballot is taken as the last day on which the ballot is open.

In most legislation, a period of months is expressed as running “from” a particular date, which is interpreted as excluding the date which defines the starting point of the period. That means that you start counting from the following day, which gives us the “corresponding date” rule. So on that basis, a period of six months from 2 November would end on 2 May.

However, that is not what the relevant legislation provides. Like the three month time limit for bringing unfair dismissal proceedings which uses similar wording, it seems that the intention of the legislation was to include the date which triggers the beginning of the period – in this case the date when the ballot closed. That means applying the “corresponding date minus one” rule, giving us 1 May in this example.

Similar issues arise when calculating periods of time expressed in days, weeks or years. Two practical tips are offered for dealing with employment time limits:

  • Don’t assume a particular time period will always be calculated in the same way.  Always check the legislation involved.
  • Don’t leave everything to the last minute: human nature being what it is, that happens all too often, but always aim to allow yourself at least an extra day’s margin.

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Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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