Set up a construction company in the UK without missing a registration

Companies House will turn you into a limited company in a few hours for £100. What that form does not tell you is that incorporation is one registration out of six, that the other five sit with HMRC, and that each of them has its own trigger and its own clock. The one with the sharpest price attached is the Construction Industry Scheme, where coming to it late costs an extra 10% of every labour payment until it is put right.

This page is the whole sequence in the order it has to happen: what Companies House needs before it will register you, which HMRC registrations your own trading behaviour switches on, what each one costs, and what goes in the diary afterwards. Every threshold and deadline names where it comes from.

What your customers see when they look you up

The public file you are about to create is read by people deciding whether to hand you money. Here is a self-builder on the BuildHub forum, setting out how he checks a construction company before he pays it:

"Firstly, a deal for goods or services is always with a legal entity usually a limited company, PLC or self-employed individual."

Alan Ambrose on BuildHub

Then the things he treats as a stop sign:

"the company doesn't exist on the companies house database or is shown as a status of dissolved, proposal to strike off, liquidation"

same thread

And what he reads once the company clears that bar:

"It's the cash level (or the lack of it) which is the trigger for liquidation"

same thread

That is a domestic client on a self-build forum, not a procurement department, and he is already reading the register, the filing status and the balance sheet. A main contractor's supply chain team does the same thing with more automation. Filings that are late, a status that says proposal to strike off, a SIC code that says something other than what you do: all of it is visible, all of it is free to look at, and all of it comes from filings you control.

The six registrations and what starts each clock

One filing at Companies House, five at HMRC. Nothing here is triggered by the calendar. Each one is triggered by something you do.

Identity verification sits alongside the first row rather than in it: it attaches to you as a person rather than to the company, it is free through GOV.UK One Login, and the incorporation will not complete without it.

Five of those six registrations are free. The whole statutory cost of getting a UK construction company legally trading is the £100 incorporation fee, and then £50 a year to keep it on the register. What costs money is missing one.

The structure decision comes first, and it is a real fork

A sole trader and a limited company do the same work on the same site and are treated very differently by the paperwork. A sole trader has no registration body to join, files no accounts, has unlimited liability, and registers with HMRC for Self Assessment once gross trading income passes the £1,000 trading allowance, by 5 October following the end of that tax year. A limited company is a separate legal person with its own tax, its own bank account and its own public file.

For a contractor the decision usually turns on three things that generic startup advice does not cover: how you get CIS deductions back, whether the main contractors you want to work for will put a sole trader on their supply chain, and what the annual running cost of the company actually is. That comparison, on those three axes, is sole trader or limited company for a builder. An accountant who works with construction clients will price your whole first year in one conversation, and it is worth the hour.

The rest of this page assumes you have picked the limited company.

What Companies House asks for before it will register you

The incorporation form is short. It is short because most of the work is deciding what goes in it.

A company name. It must be available and it must follow the naming rules in the Companies Act 2006. Some words are restricted and need supporting evidence or permission before Companies House will accept them. "Construction", "Builders", "Roofing" and the like are unrestricted. Check availability on the Companies House register before you print anything.

At least one director. Aged 16 or over, not disqualified, not an undischarged bankrupt. A company secretary is optional for a private company.

At least one shareholder. This can be the same person as the director, and for most one-person construction companies it is.

A PSC declaration. A person with significant control is anyone holding more than 25% of the shares or more than 25% of the voting rights, or who otherwise exercises significant influence over the company. In a single-director, single-share company that is you, and you say so on the form.

Memorandum and articles of association. The memorandum is a one-line statement that the subscribers are forming the company and agreeing to take at least one share each. The articles are the internal rulebook. Companies House model articles are fine for a straightforward trading company and cost nothing; bespoke articles are worth paying for when there is more than one shareholder and the share classes are doing something.

A statement of capital. How many shares, of what class, at what nominal value. £1 ordinary shares are the ordinary answer.

A registered office address. Since 4 March 2024 this must be an "appropriate address" under the Economic Crime and Corporate Transparency Act 2023: somewhere a document delivered by hand or by post would be expected to come to the attention of a person acting on behalf of the company, and where delivery is capable of being acknowledged. Companies House puts the consequence plainly: "You can no longer use a Royal Mail PO Box as your registered office address. This includes similar services from other companies." The address has to sit in the same country the company is registered in, so a company registered in Scotland needs a Scottish registered office. It is published on the public register, which is why a lot of builders working from home use their accountant's address or a formation agent's service address.

A registered email address. Also introduced on 4 March 2024. This one is not published on the register; Companies House uses it to contact the company. Use an address you will still have in five years, not the one attached to the phone contract you change every two.

A SIC code. Up to four, describing what the company does.

A lawful purpose statement. A confirmation that the company is being formed for a lawful purpose, made at incorporation and repeated each year on the confirmation statement.

Identity verification, compulsory since November 2025

Since 18 November 2025, identity verification has been a legal requirement under the Economic Crime and Corporate Transparency Act 2023. Every new director and every PSC has to be verified before the appointment can be registered.

There are two routes and they cost different amounts.

Either route produces a Companies House personal code. That code belongs to you rather than to the company, and you supply it whenever you are appointed to anything. Keep it somewhere you can find it, because you will be asked for it again on every future appointment and on every confirmation statement.

Existing companies are being brought in across a 12-month transition that started on the same date. A serving director supplies their personal code on the company's next confirmation statement, and Companies House is direct about what happens otherwise: the company cannot file its confirmation statement until all its directors are verified. A PSC who is not also a director has a separate 14-day window to supply theirs through the dedicated service. Because the confirmation statement is what keeps the company on the register, an unverified director is not a paperwork problem that waits: it is a filing block with a strike-off at the end of it.

If you are forming the company yourself, do the One Login verification first and have the personal code in front of you before you open the incorporation form. It is free, it takes about fifteen minutes with a passport or driving licence, and it removes the only step in the whole sequence that can stall an incorporation you have already paid for.

The SIC code

The SIC code is easy to fill in without thinking, by picking whatever came top of a dropdown. It is worth ten seconds of thought, because it is the field a main contractor's supply chain team, a lender and an insurer will all read to decide what you do.

Companies House uses the SIC 2007 condensed list. Section F is construction, and these are the codes a UK trading contractor is normally picking from.

You can register up to four. A groundworks firm that also does drainage and small civils might sensibly hold 43120, 42110 and 43999. Pick the one that describes the majority of your turnover first, because that is the one most systems read.

The code is not a licence and it does not limit what work you can take. It is a description, and it can be changed on the confirmation statement for nothing.

What Companies House costs, now and every year after

Fees changed on 1 February 2026. Digital incorporation roughly doubled, from £50 to £100, and the same-day service went from £78 to £156. These are the current figures.

Digital incorporation is normally through the register within 24 hours, and a postal application takes eight to ten days. Same-day incorporation is worth the extra £56 when a bank appointment, a contract award or an insurance start date is genuinely sitting on the other side of it.

The confirmation statement is the annual one that matters. It is due at least once every 12 months, covering a review period that runs from the previous statement or from incorporation, and you have 14 days after the review period ends to file it. It confirms the registered office, the directors, the statement of capital and shareholders, the SIC code, the PSC information, the registered email address and the lawful purpose, and it is now where a serving director's identity verification code is collected. The fee is charged once in each 12-month payment period, so a second statement filed mid-year to record a change costs nothing.

Not filing it is one of the few things that can genuinely end the company: it is a criminal offence, the directors can be fined up to £5,000, and the company can be struck off the register.

Then HMRC, five separate times

Companies House and HMRC do not talk to each other about any of this on your behalf. You can tick a box during digital incorporation to be set up for Corporation Tax at the same time, and that is worth doing, but the other four are yours to trigger.

Corporation Tax, within three months of becoming active

A company must tell HMRC within 3 months of the start of its accounting period that it is within the charge to Corporation Tax and is now active. Active means carrying on a business activity: trading, providing services, buying and selling with a view to making a profit, earning interest, managing investments or receiving any other income.

That definition is wider than "the first invoice went out". Taking a deposit, signing a lease or earning bank interest on the share capital can each start the clock, while genuine pre-trading setup like writing a business plan or negotiating a contract does not. If the company is dormant, tell Companies House and HMRC that instead, and the obligation is a different and much lighter one.

Corporation Tax itself is 19% on profits up to £50,000 and 25% above £250,000, with marginal relief tapering between the two. Both limits are proportionately reduced for a short accounting period and divided by the total number of associated companies, so a director who already owns another company halves both.

CIS as a subcontractor, before the first payment lands

The Construction Industry Scheme sits in Part 3, Chapter 3 of the Finance Act 2004, with the machinery in the Income Tax (Construction Industry Scheme) Regulations 2005, SI 2005/2045. If a contractor pays your company for construction operations, section 61(1) requires them to deduct tax at source from so much of the payment as does not represent the direct cost of materials. The rate depends entirely on your registration.

Registration is free, it takes minutes, and it is worth 10 points of cash flow on every labour invoice from the day it goes through. It also survives: subcontractor registration is once-only unless the structure changes, which is exactly why a sole trader who incorporates has to register the new company from scratch and cannot lean on the old record. Full mechanics in registering for CIS as a subcontractor.

CIS as a contractor, before the first subbie

The moment you pay anyone else for construction work, you are a contractor as well, and you must register as one before taking the first subcontractor on. That brings four duties: verify each subcontractor with HMRC before the first payment, deduct at the rate HMRC returns against that verification, issue a payment and deduction statement within 14 days of the tax month end (tax months run from the 6th to the 5th), and file the CIS300 monthly return by the 19th.

There is a second, quieter trigger. A business that does not do construction itself becomes a deemed contractor once its construction spend exceeds £3,000,000 in any rolling 12-month period. That catches property companies and large end users rather than most builders, and it catches them on a rolling window rather than at a year end.

PAYE, before the first payday

Register as an employer before the first payday, and no more than two months before you start paying anyone. HMRC posts the employer PAYE reference. From then on you run Real Time Information: a Full Payment Submission on or before every payday, weekly-paid site staff included.

Directors taking a salary from their own company are employees for this purpose, which is why a one-person limited company often needs a PAYE scheme in its first month. It is also the scheme through which a limited company recovers the CIS deductions taken from its own invoices, by reporting deductions suffered on the Employer Payment Summary. That route matters: a company that tries to claim its CIS back through the Corporation Tax return instead is claiming it in the wrong place.

VAT, at £90,000 on a rolling 12 months

Registration becomes compulsory once total taxable turnover in the last 12 months goes over £90,000, and you have 30 days from the end of that month to register. There is a second, faster test: if you expect turnover to exceed £90,000 in the next 30 days alone, you register by the end of that period and the effective date is the day you realised it.

The rolling test is the one that catches builders, because a single strong quarter on a commercial job can push a twelve-month window over the line while the year to date still looks small. Watch the trailing twelve months rather than the calendar year. What registration then changes about how you invoice a main contractor is the domestic reverse charge, and that is the reverse charge invoice.

The arithmetic, on one invoice and one first year

Take a limited company formed digitally on 6 April 2026, one director, one shareholder, doing first and second fix carpentry for a regional main contractor.

One invoice. You bill £10,000: £8,000 labour, £2,000 materials at direct cost. The CIS deduction applies to the labour element only, because section 61(1) of the Finance Act 2004 excludes so much of the payment as represents the direct cost of materials.

One year. Same mix, £120,000 invoiced, so £96,000 of labour across the year.

Both figures are advance payments of tax and both of them come back. The difference is timing, and £9,600 of timing is a van, a deposit on a unit, or the working capital that lets you take the next job without factoring the invoice.

What the year costs in statutory fees.

The statutory cost of a compliant UK construction company is £150 in year one and £50 a year after that. Accountancy, insurance, cards and software are separate and real, and they are where the money actually goes. The registrations themselves are near enough free, which is worth knowing before you pay a formation agent £300 for the same result.

The bank account

A limited company is a separate legal person, so the money it earns is the company's money and not yours. There is no statute that says a company must hold a business bank account, but every practical route arrives at the same place: personal account terms commonly forbid business use, and a bank will not pay a cheque or a transfer made out to a company name into an account in your own name.

There is a construction-specific reason too. The CIS gross payment business test requires that the business is carried on in the UK through a bank account. Anyone who intends to apply for gross payment status, and that is worth doing for any company with real labour turnover, needs the account open on day one with the trading history running through it. The test looks at how the business has actually operated, and a bank account opened late is trading history you cannot go back and create. What the three gross payment tests ask for, and in what order to fix them, is gross payment status.

Open the account once the certificate of incorporation arrives. Most banks want the certificate, the company number, the directors' and PSCs' identification, and a description of the trade that matches the SIC code you registered.

Insurance, before the first day on site

Employers' liability is compulsory. Under the Employers' Liability (Compulsory Insurance) Act 1969 you must hold it as soon as you become an employer, for at least £5 million, from an authorised insurer. The certificate has to be available to employees, on the wall, the intranet or the website, and produced to an inspector on request. Trading uninsured is £2,500 for every day you are not properly covered, and failing to display or produce the certificate is a further £1,000. Two narrow exemptions exist: a business whose only employees are close family members, and employees based outside England, Scotland and Wales. HSE's guidance on the Act also puts outside the requirement a company whose only employee owns 50% or more of the issued share capital, which is a lot of one-person construction companies in their first year.

Public liability is not statutory, and it is still non-negotiable. Principal contractors normally require £5 million or £10 million, domestic clients ask for it, and local authority and housing association frameworks set the figure in the tender documents. Under a JCT contract the number is not market practice at all: it is written into the Contract Particulars at clause 6.4.1, so the contract decides the limit. Read the number in the contract before you buy the policy, because holding £2 million and then being asked for £10 million on award is an expensive week.

Contract works covers the works under construction, the materials, the temporary works and the site plant, and it is separate from cover on the existing building. Tool and plant cover is where small claims are won or lost, on the overnight-theft-from-a-vehicle wording and the single-article limit. Professional indemnity enters the moment you design as well as build, which includes a contractor's designed portion and anything where you produce the detail.

The cards and the schemes

Registration makes the company legal. Cards make it able to get through the gate, and they are two different systems that get confused with each other constantly.

CSCS and the other card schemes are contractual. Site access on a principal contractor's job is normally gated on a valid card because the principal contractor's site rules say so, not because a statute does. The route to one is a relevant qualification, usually an NVQ or SVQ at the right level for the occupation, plus a CITB Health, Safety and Environment test passed within the two years before you apply.

Gas Safe is law. Work on gas fittings and appliances is restricted under the Gas Safety (Installation and Use) Regulations 1998 to businesses on the Gas Safe Register. This is a registration of the business as well as the engineer, so it belongs in this sequence rather than in a personal training plan.

Part P gates the notification, not the person. Notifiable domestic electrical work in England and Wales has to be certified, either by notifying building control or by being a member of a government-authorised competent person scheme that lets you self-certify. It does not apply in Scotland, where Building Standards 4.5 and 4.6 cover the same ground, and there is no statutory equivalent in Northern Ireland.

Which cards and schemes apply to your trade, and what a main contractor's supply chain team will actually ask to see, is on the UK trade rules page.

The order to do them in

1. Pick the structure. Sole trader or limited company, decided on how CIS money comes back and what your customers will accept.
2. Verify your identity through GOV.UK One Login. Free, and it has to be done before an appointment can be registered. Save the personal code.
3. Incorporate. Name, director, shareholder, PSC declaration, articles, statement of capital, appropriate registered office, registered email address, SIC code, lawful purpose. £100 digital, normally through within 24 hours.
4. Open the business bank account as soon as the certificate arrives, and run everything through it from the first payment.
5. Register for CIS as a subcontractor before the first contractor payment reaches you. This is the one worth 10 points of cash on every labour invoice.
6. Register for Corporation Tax within 3 months of the accounting period in which the company becomes active, unless you ticked the box during incorporation.
7. Buy employers' liability cover the day you have an employee, and public liability to the figure your contracts specify.
8. Register as an employer for PAYE before the first payday, your own director's salary included.
9. Register as a CIS contractor before the first subcontractor, and verify before you pay anyone.
10. Watch the trailing twelve months against £90,000 and register for VAT within 30 days of the end of the month you cross it.
11. Put the recurring dates in the diary on the day the company is formed, not the week they fall due.

The dates that stay in the diary

Two of those rows move under Making Tax Digital, and a sole trader with qualifying income over £50,000 has been inside it since 6 April 2026 with quarterly updates instead of one annual return. What changes, when, and at which turnover threshold is Making Tax Digital for construction.

One more date worth knowing early: from 1 April 2028 all accounts filed at Companies House must go in through commercial software in iXBRL format, and the web and paper routes close. Small companies and micro-entities will file a profit and loss account, with the option not to publish it. Software you are already using will handle that, which is an argument for choosing it in year one rather than in 2028.

What it costs

AEC Stack has no monthly subscription. The platform fee is 2.5% of each invoice processed through the platform, taken when the invoice is paid, so a month with no invoices costs nothing.

Your company details, the registrations you have completed and the ones your trading has just triggered sit in one place, with the recurring dates counted from the figures you entered rather than from a generic checklist. Your invoices carry the labour, materials and plant split that the CIS deduction is worked out from, so the deduction on each payment is right before it goes out rather than argued about a month later.

Put your company details in and see which of the six registrations your trading has already triggered: start here.