Short answer: yes, they count. The 30 days you have to acknowledge a data protection complaint are calendar days, and weekends and bank holidays do not extend the deadline. This guide shows how to count correctly and where organisations most often trip.
Calendar days, not working days
Section 164A(3) of the Data Protection Act 2018 gives you 30 days from receipt to acknowledge a data protection complaint, in force from 19 June 2026.[2][6] The statute says "30 days" without qualification, and the ICO's February 2026 guidance treats the figure as a calendar-day count.[4]
That matters because a lot of UK regulatory and contractual deadlines are expressed in working days, and it is easy to assume this one is too. It is not. Every day counts — Saturdays, Sundays, bank holidays, your Christmas closedown. A deadline that lands on a bank holiday is still the deadline; it does not roll to the next working day.
A worked example
A complaint arrives by web form on Wednesday 1 July 2026. Counting 30 calendar days from receipt, you must acknowledge it by Friday 31 July 2026.[2]
If your team works Monday to Friday, that 30-day span contains only about 22 working days — and if a bank holiday or a holiday closedown falls inside it, fewer still. The statutory clock does not care. Nine weekend days inside the window are nine days you cannot use, but they are nine days that still elapse.
The trap: the clock starts on receipt, not awareness
The more damaging mistake is not miscounting weekends — it is miscounting the start. The 30 days run from when the complaint reaches your published channel, not from when someone inside the organisation reads it.[2] A complaint that sits unread in a shared info@ inbox over a long weekend has already burned those days against the clock.
Combine that with calendar-day counting and the risk compounds: a complaint received late on the Friday before an August bank holiday, into an inbox nobody checks until Tuesday, has quietly lost three or four days before anyone in the organisation has seen it. The duty implies an obligation to monitor the channels you have held out as receiving complaints, cover included.
How to stay clear of the deadline
Three habits remove almost all of this risk:
- Acknowledge early, not on day 30. Aim to acknowledge within the first few working days of receipt. The earlier you acknowledge, the more of the calendar-day window is irrelevant to you. See how to acknowledge a data protection complaint.
- Stamp the receipt date automatically. Record when a complaint arrives, on every channel, independently of when it is read — so the clock is counted from the right day and holiday gaps cannot hide it.
- Plan cover around closedowns. Weekends, bank holidays and your own holiday periods do not pause the duty, so make sure someone is watching the complaint channels across them, with an audit trail of the checks.
The deadline itself is simple. The failures come from counting from the wrong day and from assuming a quiet office pauses a duty that runs on the calendar.
Frequently asked questions
Is the 30-day complaint deadline in calendar days or working days?
Calendar days. Section 164A(3) of the Data Protection Act 2018 says 30 days without qualification, and the ICO's February 2026 guidance treats it as a calendar-day count.[2][4] Weekends and bank holidays are included.
What happens if the deadline falls on a weekend or bank holiday?
It does not move. Unlike some working-day deadlines, the 30-day acknowledgement deadline does not roll forward to the next working day.[2] Plan cover so a complaint received before a closedown is still acknowledged in time.
When does the 30-day clock actually start?
On receipt — when the complaint reaches your published channel — not when someone reads it.[2] A complaint left unread in a shared inbox is already using up its window.