Portable Appliance Testing (PAT testing) checks that electrical appliances — kettles, laptops, extension leads, workshop tools — are safe to keep using. It's one of the most routine parts of electrical compliance for offices, shops, HMOs and rental properties across London, and it's often the first thing an insurer or council inspector asks to see evidence of.
This guide covers what PAT testing actually involves, who's legally expected to arrange it, how often different appliances need testing, and what determines the cost of a visit in London.
What PAT Testing Covers
A PAT test combines a visual inspection of the plug, cable and casing with a set of electrical tests — earth continuity, insulation resistance and, where relevant, a functional check to confirm the appliance actually operates as intended. Each appliance that passes is labelled with the test date and next due date, so anyone checking the equipment later can see at a glance when it's due again.
Who Needs PAT Testing
There's no single law that names "PAT testing" specifically, but the Electricity at Work Regulations require equipment to be maintained in a safe condition. In practice, PAT testing is the standard way businesses and landlords demonstrate they've met that duty for portable appliances, alongside a valid EICR for the fixed installation.
| Property or Business Type | Typical PAT Testing Need |
|---|---|
| Offices and shops | Regular testing to meet employer duty of care |
| Rental properties | Required for any landlord-supplied appliances |
| HMOs | Shared kitchen and communal appliances, often reviewed at licensing |
| Workshops and trade premises | More frequent testing for handheld power tools |
How Often Appliances Should Be Tested
Testing frequency depends on the appliance type and how it's used, not a single fixed interval. Higher-risk items — power tools, extension leads, equipment used in a workshop or kitchen — are tested more often than low-risk equipment like a desk lamp, because they're moved more, plugged and unplugged more, and exposed to more wear.
| Equipment Category | Example | Typical Testing Frequency |
|---|---|---|
| Handheld | Drills, hairdryers, kettles | Most frequent — highest wear and handling |
| Portable | Heaters, monitors, fans | Moderate — moved occasionally |
| IT equipment | Laptops, printers, monitors | Least frequent — rarely moved, low current |
We assess your appliances and set a sensible testing schedule based on this kind of risk grading, rather than applying one blanket interval to everything on site.
What Happens During a Visit
We test each appliance in turn, label it, and record the result against an asset register. Any appliance that fails is flagged immediately so it can be repaired or replaced before it's used again, rather than being left in service until the next scheduled visit.
What We Check During a Visit
- Visual check of plug, cable and casing for damage
- Correct fuse rating for the appliance
- Earth continuity (for Class I appliances)
- Insulation resistance
- Functional check where appropriate
What a Fail Means
A failed appliance usually has a damaged cable, an incorrect fuse rating, or a fault inside the casing. We tell you exactly what failed and why, so you can decide whether to repair or replace it, rather than just receiving a pass/fail number with no explanation.
Categories of Equipment We Test
Appliances are generally grouped into three risk categories: handheld (drills, hairdryers), portable (kettles, heaters, monitors) and IT equipment (laptops, printers). Handheld tools carry the highest risk because of how they're used and are tested most frequently; IT equipment, which is rarely moved and runs at low current, needs testing less often.
Record Keeping and Documentation
Every test result is logged against an asset register — appliance type, location, pass/fail, and next due date. This register is what you'd show an insurer, a council inspector, or a new tenant as evidence of compliance, so keeping it up to date after every visit matters as much as the testing itself. It sits alongside the records covered in our commercial electrical compliance guide.
PAT Testing for Landlords and HMOs
Landlords who supply appliances with a rental property — a fridge, kettle, washing machine or microwave — have a duty to keep them in a safe condition, and PAT testing is the accepted way to evidence that. This sits alongside, not instead of, the wider requirements covered in our guide to landlord electrical safety certificates, which focuses on the fixed installation rather than the appliances themselves.
What Affects PAT Testing Cost in London
Cost is driven by the number of appliances, the mix of equipment types (handheld items take longer to test than IT equipment), and how spread out they are across a site. A single office with fifty desk-based items is usually quicker to test than the same number of items spread across several small workshops. As with an EICR, the only reliable quote is one based on your actual appliance count and site layout rather than a generic per-item price.
| Cost Factor | Effect |
|---|---|
| Number of appliances | Directly scales total testing time |
| Mix of equipment types | Handheld items take longer per unit than IT equipment |
| Site layout | Equipment spread across several rooms or floors adds time |
| Failed appliances found | May add follow-up costs for repair or retest |
Booking a PAT Testing Visit
Tell us the number and type of appliances, and where they're located, and we'll confirm how long the visit will take and what it will cost. For sites that also need an EICR or fire alarm checks, booking everything together in one visit is usually more efficient than arranging separate call-outs.
For further reading on the legal basis for appliance safety at work, see the HSE's FAQs on portable appliance testing.
PAT Testing vs an EICR
PAT testing and an EICR are often confused, but they cover different parts of a property's electrical safety. PAT testing checks portable appliances that plug into sockets — anything that can be unplugged and moved. An EICR checks the fixed installation itself: the wiring, consumer unit and circuits that stay in place. Most commercial and rental properties need both, on their own separate schedules, to be fully compliant.
| PAT Testing | EICR | |
|---|---|---|
| What it covers | Portable, plug-in appliances | Fixed wiring and consumer unit |
| Typical frequency | Varies by risk category | Every 5 years for rentals |
| Output | Pass/fail label per appliance | Coded report (C1, C2, C3, FI) |
Why PAT Testing Matters Beyond Compliance
Beyond meeting a legal duty of care, up-to-date PAT testing records are one of the first things an insurer will ask for after an electrical fire or fault involving portable equipment. Without evidence that appliances were checked and maintained, a claim can be delayed or disputed. The same records also reassure staff, tenants or visitors that the equipment they're using day to day has actually been checked, not just assumed to be safe.
Common Misconceptions About PAT Testing
A few misunderstandings come up regularly. New appliances still need testing before first use in a commercial setting — a CE or UKCA mark on the box confirms the appliance met safety standards when manufactured, not that it's still safe after months or years of use. Passing a visual check alone isn't the same as a full PAT test — internal faults like degraded insulation don't always show on the outside. And a appliance that "still works fine" isn't automatically safe; some of the most common faults found during testing don't affect day-to-day function until they cause a shock or fire.
Preparing for a PAT Testing Visit
A visit runs faster and more smoothly with a little preparation. Having an existing asset list or count of appliances ready, making sure equipment is accessible rather than pushed against walls or hidden in cupboards, and flagging any appliances that have had recent repairs all help the visit go efficiently. For larger sites, grouping appliances by room or department in advance can also cut down on testing time.
DIY PAT Testing vs a Qualified Electrician
PAT testers are available to buy, and in principle anyone can run a test. In practice, correctly interpreting the results — knowing what insulation resistance or earth continuity readings actually mean, and applying the right test to the right appliance class — takes training. A qualified electrician also keeps consistent, dated records in a format that insurers and councils recognise, which matters more than the test itself when it comes to demonstrating compliance later.
PAT Testing Frequency by Business Type
While risk category drives testing intervals for individual appliances, the type of business or property also shapes how often a full site visit makes sense. A busy commercial kitchen with kettles, microwaves and toasters in constant use benefits from more frequent checks than a quiet reception area with a phone and a printer. Below is a general guide to how frequency tends to vary by setting, though the right interval for any specific site depends on actual usage and appliance condition rather than the category alone.
| Setting | Typical Appliance Mix | Relative Testing Frequency |
|---|---|---|
| Offices | Laptops, monitors, kettles | Annual, in most cases |
| Retail and hospitality | Kitchen equipment, tills, display units | More frequent, due to public-facing use |
| Construction and trade sites | Power tools, extension leads | Most frequent, due to heavy handheld use |
| Rental properties and HMOs | Landlord-supplied white goods | Typically aligned with tenancy changes |
What Happens If You Skip PAT Testing
There's no direct fine for not carrying out PAT testing itself, since it isn't named in law as a standalone requirement. The risk instead sits with the underlying duty of care: if an untested appliance causes an injury, a fire, or property damage, the absence of any testing record makes it much harder to show that reasonable steps were taken to keep equipment safe. Insurers may also decline or reduce a claim where no maintenance evidence exists, and councils reviewing an HMO licence or commercial premises may treat a lack of records as a compliance gap in its own right.
Getting a Fair PAT Testing Quote
Because cost scales with appliance count and site layout rather than a flat rate, the most useful thing you can do before requesting a quote is have a rough count of appliances by type ready. A quote based on real numbers, rather than an estimate per square metre or per employee, gives a more accurate picture of both cost and how long the visit will take — and avoids surprises once testing is under way.
Frequently Asked Questions
Is PAT testing a legal requirement?
There's no law that names PAT testing directly, but the Electricity at Work Regulations require electrical equipment to be kept safe — PAT testing is the accepted way to demonstrate that.
How long does PAT testing take?
It depends on the number of appliances. A small office might take under an hour; a larger site with more equipment takes longer.
What's the difference between PAT testing and an EICR?
PAT testing covers portable appliances that plug into sockets. An EICR covers the fixed electrical installation — the wiring, consumer unit and circuits themselves.
Do landlords need PAT testing?
If a rental property is let with appliances supplied by the landlord, those appliances should be kept in a safe condition, and PAT testing is the standard way to check and evidence that.
