An attendance machine is the device on the wall that records who arrived and when. Choosing one in the UK is mostly two decisions: which reader survives your workplace, and whether you are willing to take on biometric data.
Match the reader to the room, not the brochure
Card and fob readers are quick, cheap and unbothered by dirty hands. Fingerprint readers struggle with wet, cold or worn fingers, which describes most of the trades that want them. Facial readers cope with gloves but need consistent lighting and a sensible mounting height. Stand where people queue at shift change and choose the reader that copes with what you see.
Biometrics bring duties that a card does not
Data used to identify someone by a physical characteristic is special category data under UK data protection law, and using it requires more than a decision that it would be convenient. You need to be able to state the lawful basis, tell people clearly what is collected and why, keep it no longer than needed, and offer a workable alternative to anyone who objects.
A data protection impact assessment is the sensible starting point
The ICO expects employers to assess monitoring before introducing it, and the exercise is genuinely useful rather than paperwork: it forces you to write down what the machine collects, who sees it, how long it is kept and what less intrusive option was considered. It is also the document that answers a complaint months later, when nobody remembers the reasoning.
Think about where the record goes next
Most attendance machines are bought to save time at the payroll cutoff, so the export matters as much as the reader. Check it writes a file your payroll accepts, test it with a real period, and find out what you can retrieve if you change supplier. A machine that keeps its record in a proprietary format on a wall is a problem waiting for an audit.
Questions people ask about attendance machine
Can staff refuse to use a biometric machine?
In practice you need a workable alternative. Objections are much easier to handle if the alternative was designed in rather than improvised.
Is a card reader enough?
For most workplaces, yes. It gives the same electronic record without special category data obligations.
Do we need to tell staff before installing?
Yes. Clear information before monitoring begins is a basic expectation, and it is much easier than explaining afterwards.