Electrical work hides itself. Within a week of completion the cables are behind plaster and under floors, and the only remaining evidence of how it was done is paperwork. That makes the checks you do beforehand unusually valuable, and the warning signs unusually specific.
A registration you cannot find
Start here, because it is the cheapest check and the most decisive. Search the exact company name on the quote at electricalcompetentperson.co.uk, or on the scheme searches directly.
What matters is the exact legal entity. If the quote comes from a limited company and the registration is held by a sole trader, or the name on the van is a trading style nobody has registered, the registration does not attach to the party you are contracting with.
Then check the scope. Registration for domestic notifiable work is not the same as registration for condition reporting, and the tiers carry different insurance requirements. Someone offering a condition report while registered only for domestic installation work is operating outside their scope.
Vagueness in response to this question is itself the answer. A registered electrician knows their registration number and expects to be checked.
No answer on who notifies the work
Installing a new circuit, replacing a consumer unit, or altering circuits in the defined space around a bath or shower are all notifiable in England. Someone has to tell the local authority.
Ask which of those applies to your job, who is notifying it, and what certificates you will receive. A registered electrician self-certifies and the scheme notifies the council. An unregistered one has to arrange building control before starting, which costs a fee and adds an inspection.
The bad answer is that it does not need any of that. On a consumer unit change or a new circuit, that answer is wrong, and it usually means the work will finish without paperwork.
Watch for the reverse error too. Being told a job is notifiable when it is not is either poor knowledge or a way of inflating a quote. A socket added to an existing circuit outside a special location is one example, and so is work in a kitchen, which is not a special location in England.
Findings misdescribed to sell remedial work
This one is specific to electrical work and it is worth understanding properly, because it is hard to argue with when you do not know the codes.
Condition report codes come from IET Guidance Note 3, Table 3.5. A C1 is danger present. A C2 is potentially dangerous. An FI means there was not enough information to judge. A C3 means improvement recommended, with no danger present, and it is advisory only.
Any C1, C2 or FI makes a report Unsatisfactory. C3 items alone do not. So a report full of C3 observations has passed.
Being told that a list of C3s means your installation has failed and needs rewiring is the most common upsell in this trade. Ask to see the codes against each observation, and ask which specific ones drove the overall assessment. An honest inspector explains that readily. Someone quoting for the remedy before explaining the finding is doing it in the wrong order.
The same logic applies to a consumer unit. A board change is a legitimate upgrade and an easy thing to sell, and the difference is whether anyone tested the installation before recommending it.
Certification treated as optional
The paperwork question separates competent from careless faster than anything else on site.
Any addition or alteration should produce a Minor Electrical Installation Works Certificate at minimum, recording the testing of the affected circuit. New circuits and consumer unit changes produce an Electrical Installation Certificate, plus a Building Regulations Compliance Certificate issued by the scheme where the work is self-certified.
An electrician who treats certification as an optional extra, or who cannot say which document a job produces, has told you they do not test systematically. Approved Document P is clear that even non-notifiable work should be inspected, tested and certificated in accordance with BS 7671.
Sales patter that does not survive checking
Urgency built on a supposed regulatory deadline is worth verifying rather than acting on. The wiring regulations are a British Standard, not law, and their current version is an amendment to the 18th Edition published in April 2026. There is no 19th Edition, so a pitch built on being "19th Edition qualified" is selling a qualification that does not exist.
Equally, no rule requires an owner-occupier to hold a condition report, and no law compels rewiring at any particular age. Both claims circulate.
Money and paperwork
Paying cash is legal, and a sole trader under the £90,000 taxable turnover threshold charges no VAT at all, which is a legitimate reason two honest quotes differ by a fifth. What is not legitimate is a VAT-registered firm switching the VAT off.
The tell is never the discount, it is the invoice. A lower price with paperwork is fine. A lower price conditional on there being no paperwork removes your evidence of who did the work, on what terms and when. On this job the physical evidence disappears behind plaster.
On deposits, the consumer guidance is to keep them as small as possible and not to agree to more than 25%. That figure is guidance rather than law, and the reasoning holds: an upfront payment is a contribution towards materials, not payment for labour that has not happened.
Insurance you cannot verify
Certificates are easy to fake. Ask for the policy schedule or for the broker to confirm directly, check the insurer is authorised on the Financial Services Register, check the named party matches the company on your quote, and check the dates cover your whole project.
Electrical work hides behind plaster, so the warning signs are almost all administrative rather than visible: the registration, the insurance and the certificate are what you have instead of being able to see the cables.