
How often should PAT testing be done? There is no single figure that covers every appliance, however often the question gets asked that way. The honest answer is that it depends on the equipment, the environment it sits in, and how much handling it gets — which is the shape the actual guidance takes, rather than one fixed period stamped on every certificate.
Why the interval isn't fixed
PAT testing itself isn't named directly in law — the duty is to keep electrical equipment in a safe condition, and testing is how that gets evidenced. The same principle carries through to frequency: nothing in the regulations sets a blanket interval, because a kettle in a busy staff kitchen and a monitor that hasn't moved from a desk in two years don't carry the same risk of developing a fault.
What actually sets the interval
- The environment — equipment used outdoors, on a building site, or somewhere it gets knocked about and dragged through mud needs checking far more often than the same item sitting in an office.
- The appliance class — Class I equipment, the kind with an earth pin, generally gets tested more frequently than double-insulated Class II equipment, because there is an earth path that can fail as well as the insulation.
- How much it's handled — leads and portable tools that get plugged in, unplugged, coiled and dragged around all day tend to fail sooner than something that sits untouched in one socket.
- Its own history — an item with a clean run of passes can often go longer between tests than one that has already failed once or been repaired.
Put those together and the same building ends up with different intervals for different things in it — a kettle in the kitchen tested more often than the desktop monitors two rooms away, even though both sit under the same roof.
Construction sites at one end, quiet offices at the other
Equipment on a construction site typically gets tested most often of anywhere, because that environment does more damage to a cable or a casing in a week than an office does in a year. A quiet office full of laptop chargers and monitors that rarely leave their desks sits at the other end, and many businesses combine that with a simple visual check between full tests. Where your own equipment falls on that scale is not something to guess at — it is what a proper assessment of how the kit is actually used is for.

What the sticker and the certificate are actually for
Every item that passes gets a small sticker near the plug, and it is worth treating that as more than a pass mark — it is the quickest way to see when an appliance is next due without digging out any paperwork. The certificate that comes with the visit is the fuller record: every item tested, what it was, and when it was done, which is what an insurer or an inspector will actually want to see if the question is ever raised. Keep both — the sticker tells you at a glance, and the certificate is what proves it if you are asked.
We carry out PAT testing across London, Essex and north Kent, and we set a testing schedule around your equipment and how it is used rather than handing you the same interval as everyone else.
If you are unsure, it is always cheaper to ask than to guess. Give us a call and we will tell you straight.
