Before you sign or pay a deposit, one question deserves two minutes: does the company on the quote actually exist, is it active, and does the register show anything you should know? The reality check on the paperwork, straight from Companies House. Workmanship it cannot judge; warnings it can.
A clean register is step one of three. Judge the quote itself with the quote check and why quotes differ, and nail the agreement down with the contract checklist before you sign. Deposits small, payments per completed stage, and the final instalment after snagging; that discipline protects you more than any register can.
A company check against the Companies House register: search the builder from your quote, pick the right company, and read a traffic-light report on the register facts before any money moves.
Five things from the public register: whether the company exists and is active, how long it has been registered, whether the legally required accounts are filed on time, whether there is insolvency history under this company number, and whether the registered activities are construction. Each comes back as good, ask-about-this, or warning, with what it means in plain words.
Whether the work will be good. Companies House knows the paperwork, not the plastering. A clean record is a necessary condition, not a sufficient one: combine it with references you actually call, photos of previous jobs, and quotes judged against an independent range.
Not automatically. Sole traders and ordinary partnerships do not register at Companies House, and many excellent tradespeople work that way. What changes is what you can check: there is no register to look up, so references and a written agreement matter even more, and the name on the quote should match the name you pay. A sole trader is personally responsible for all the debts of the business (gov.uk, Set up as a sole trader, read 27 September 2026).
The exact legal name on the quote, ideally with the company number, which any limited company must show on its paperwork. The name on the van is often a trading name; if the quote shows no legal name or number at all, that is itself a fair question to ask before anything else.
After a free report you can run the full check on the same company. It reads more of the register: the directors and what happened to their other companies, loans secured on the company, a strike-off announced in the Gazette, moves of the registered office, a recent name change and the kind of accounts filed.
An AI model then writes the questions to ask before you sign, and that model is what costs me money per check. One full check a month is free. After that it comes out of the Renovation Pack (£19.95, 5 full checks plus the quote checks and AI images) or a single check for £4.95. For the written part, the register findings (not your details) go to the AI provider; nothing is stored.
Free, with a fair daily limit against abuse. Your search goes to the public Companies House register and nowhere else; it is not stored, not linked to you, and there is no account and no email.