Outsourcing vs In-House PAT Testing: Which Is Right for Your Organisation?

The decision to outsource PAT testing or manage it internally is not purely about cost. It is about who is competent to do the work, how much organisational overhead you can absorb, and how your testing programme will be documented and managed over time.

Both approaches are valid. The law does not require you to use a professional contractor. What it requires — under the Electricity at Work Regulations 1989 and the Provision and Use of Work Equipment Regulations 1998 — is that the person doing the inspection and testing is competent to do so safely.

What "competent" means in this context

The IET Code of Practice for In-Service Inspection and Testing of Electrical Equipment (5th edition) defines competence in terms of: knowledge of the Code of Practice, appropriate training, and experience of the type of equipment being tested.

It does not define a specific qualification as mandatory. However, in practice, someone conducting formal combined inspection and testing (the full PAT test) should have formal training — typically City & Guilds 2377 (In-Service Inspection and Testing of Electrical Equipment; the current award is the 2377-77 Level 3) or equivalent. This is not a legal minimum; it is the practical baseline that allows you to demonstrate competence if challenged.

Visual-only inspections (without test equipment) require a lower bar of competence. A trained and responsible employee can carry these out after appropriate instruction, without any formal electrical qualification.

When outsourcing makes more sense

You have a large appliance inventory or multiple sites. A contractor with a full team and calibrated test equipment can process hundreds of appliances in a day. Building an in-house capacity to do the same would require equipment purchase, training, and staff time that is difficult to justify for an annual cycle.

You need third-party documentation. Some insurers and some regulated environments (healthcare, childcare) specifically want test results from an external assessor, not an internal one. If your insurer or contract requires independent certification, outsourcing may not be optional.

You have very high-risk equipment. Power tools, equipment used outdoors, or equipment in wet environments typically needs more rigorous testing. A professional contractor with appropriate calibrated equipment can carry this out reliably. The IET Code of Practice recommends higher testing frequencies for this equipment type — three months for portable equipment used on construction sites, for example — making the administrative case for outsourcing stronger.

Your test cycle is infrequent. If you are testing a small office's equipment annually and have no staff qualified to do it, a contractor visit once a year is simpler than building internal capability.

When in-house makes more sense

You have a continuous need, not an annual one. If you bring in new equipment regularly — event hire companies, production facilities, office environments with frequent new hires — an annual contractor visit does not cover you between cycles. An in-house programme with trained staff who can inspect and log new equipment as it arrives is a better fit.

Your appliance count is moderate and equipment is low-risk. A 200-appliance office inventory of laptops, monitors, phone chargers, and kitchen equipment is perfectly manageable in-house with a trained member of staff and a PAT tester device. The equipment cost (a basic PAT tester runs from £150 to £800 depending on capability) pays back quickly against contractor costs.

You want more control over timing and records. Contractor visits create a snapshot of a single day. An in-house programme can update the register continuously, flag failures in real time, and track disposals or new additions without waiting for the next scheduled visit.

You have a maintenance function already. Facilities managers, site managers, or maintenance staff who already manage other compliance programmes often absorb PAT testing with minimal additional overhead once trained. The programme fits naturally into existing maintenance scheduling.

The cost comparison

Contractor pricing varies significantly by region, volume, and appliance type. As indicative ranges only (obtain quotes to establish current market rates):

Small office, 50–100 appliances: £100–£250
Medium business, 200–400 appliances: £200–£600
Large site, 500+ appliances: £500+, often negotiated on a per-item rate of £1–£3 per appliance

These are one-visit estimates. A professional contractor's cost over three years for a 200-appliance office at typical re-test intervals might total £600–£900 as a rough guide — actual costs depend on your location, contractor, and equipment mix.

For in-house: a PAT tester device (indicative range: £150–£800 depending on capability), one day of City & Guilds 2377 training (indicative range: £150–£300), and staff time each year. Capital cost typically recovers in roughly two to four annual cycles.

Use the PAT testing cost calculator to run your specific numbers against the main cost variables.

What changes when you go in-house

The paperwork responsibility shifts entirely to you. When a contractor tests your equipment, they provide a test certificate and a register of results. You keep a copy and the burden of proof rests partly on their paperwork.

When you test in-house, your own register IS the compliance evidence. This means:

Your log needs to be complete, well-structured, and retained properly
The person doing the testing needs documented training
Any failures need a documented disposition (quarantined, repaired, disposed of)

The PAT testing log book guide covers what a compliant in-house record needs to contain.

The PAT testing procedure guide covers how to structure an in-house programme.

A hybrid approach

Many organisations with significant appliance counts use both: a contractor visits annually to perform formal combined inspection and testing on the full inventory, while trained internal staff carry out formal visual inspections on new equipment and on appliances that show visible damage between cycles.

This captures the efficiency of contractor scale with the responsiveness of in-house oversight. The key requirement is that the hybrid programme is documented coherently — not two separate record systems that do not cross-reference.

What to look for in a contractor

If you outsource, the contractor's competence matters as much as their price. Before engaging a PAT testing contractor:

Ask for evidence of relevant qualifications for the testing staff (City & Guilds 2377 or equivalent)
Check that their test equipment is calibrated and that calibration certificates are current
Ask for a sample test certificate to confirm the format and content of what you will receive
Check that their insurance covers public liability while on your premises

For a full guide to hiring a PAT tester, including the right questions to ask and red flags to avoid, see how to hire a PAT tester.

The information in this post reflects UK law as of the date last reviewed. Regulations change. Check legislation.gov.uk for current statutory text and HSE.gov.uk for current guidance before making compliance decisions.