Setting up a limited company in the UK means incorporating through Companies House — a process that takes 15–30 minutes online, costs £50 (per GOV.UK), and creates a separate legal entity that protects your personal assets from business debts. Seven post-formation steps then determine whether the company runs cleanly from day one.
What do you need before registering a limited company?
Before you open the Companies House incorporation service, gather five things: a confirmed company name, a registered office address, at least one director's details, the correct SIC code, and a clear share structure. Missing any of these mid-filing wastes time and can lead to errors that take weeks to correct on the public register.
Company name. Run the name through the Companies House name availability checker. The name cannot be identical or too similar to an existing registered name, cannot include sensitive words (bank, royal, national, chartered) without prior approval, and must end with "Limited" or "Ltd". Check the domain and the Intellectual Property Office trademark register at the same time — all three need to clear before you commit.
Registered office address. This must be a physical UK address in the same country as your incorporation (England and Wales, Scotland, or Northern Ireland). It becomes part of the public Companies House register and receives all statutory correspondence from HMRC and Companies House. Most founders use an accountant's address or a registered-office service rather than their home address.
Director details. You need the full legal name, date of birth, nationality, occupation, service address, and residential address of each director. The residential address is kept private by Companies House; only the service address appears publicly. Every company needs at least one director who is a natural person aged 16 or over.
SIC code. A Standard Industrial Classification code describes what the company does. You can have up to four. Choose the most accurate description — a wrong SIC code does not invalidate the company, but it can look sloppy to banks and investors and occasionally triggers HMRC enquiries. Search the Companies House SIC list before you start.
Share structure. Decide how many shares to issue and to whom. A simple single-founder setup typically uses 100 ordinary shares at £0.01 or £1.00 each — the total share capital (usually £1 or £100) is less important than getting the percentage split right from the outset. If there are two or more founders, agree equity percentages and a shareholder agreement in writing before you incorporate.
How do you register a limited company with Companies House?
The standard route is the Companies House online incorporation service. The fee is £50 per GOV.UK, payable by debit card or credit card, and the application takes 15–30 minutes if you have all the information prepared. Most applications are processed within 24 hours; many complete within a few working hours.
If you need the company incorporated the same day — for example, to open a bank account or sign a contract — Companies House offers a same-day service for £71 per GOV.UK, available until 3pm. The certificate arrives by email on the same working day.
The alternative is filing through an authorised Companies House formation agent or your accountant using the software-filing route. This costs £12 for the Companies House fee alone, though formation agents add their own service charge on top. The advantage is that an accountant-led formation typically bundles post-formation admin — HMRC registration, registered office, bookkeeping setup — into a single onboarding package.
| Filing route | Fee | Speed | Best for |
|---|
| Companies House online (standard) | £50 | 24 hrs (often same day) | DIY founders |
| Companies House same-day service | £71 | Same working day | Urgent incorporations |
| Software-filing (via agent/accountant) | £12 + agent fee | 24 hrs | Full-service onboarding |
| Postal (paper IN01) | £71 | 8–10 working days | Rarely needed |
All fees per GOV.UK / Companies House, May 2026.
What do you need to do after registering a limited company?
Most founders celebrate the certificate email and then do nothing for weeks. That is the single biggest risk in the formation process. Seven post-formation steps are legally required or practically essential — and several have hard deadlines.
1. Register for Corporation Tax
- · Must register with HMRC within 3 months of starting to trade — per GOV.UK
- · Do it via the company's Government Gateway account
- · Late registration attracts penalties; HMRC will eventually find you anyway
2. Check VAT registration
- · Mandatory if turnover exceeds £90,000 in a rolling 12-month period (per HMRC)
- · Voluntary registration below the threshold is worth considering if your customers are VAT-registered businesses
- · Register online via HMRC
3. Open a business bank account
- · A limited company is a separate legal entity — it must have its own account
- · UK challenger banks typically open within one working day
- · Using a personal account mixes finances and destroys the limited-liability protection
4. Set up bookkeeping
- · Connect accounting software (Xero, QuickBooks, FreeAgent) to the new bank account from day one
- · Cleaning up retroactive records costs far more than doing it right from the start
- · Keep all receipts from the first transaction
5. Register as an employer
- · Required before running any payroll, including a director's salary
- · Register with HMRC's PAYE service before the first payday
- · Director-only payrolls are common even if no employees are hired
6. Maintain statutory books
- · Every company must keep a register of directors, members, and PSCs
- · These can be kept at the registered office or at Companies House
- · Failure to maintain them is a criminal offence per the Companies Act 2006
7. Review the Articles of Association
- · Model Articles (the Companies House default) are fine for a single-founder, single-share-class setup
- · If you plan to take investment, issue preference shares, or set up a co-founder vesting schedule, bespoke articles drafted by a solicitor are worth the cost
- · Amending articles later requires a special resolution — it is far simpler to get them right at formation
What mistakes do new limited company directors make?
Wrong SIC code. Choosing a vague or inaccurate SIC code does not prevent incorporation, but it can trigger questions from banks and investors, and it looks unprofessional on the public register. Spend two minutes finding the most accurate match.
Home address as registered office. This is legal but makes your home address permanently visible on Companies House. From March 2024, directors can apply to suppress residential addresses that were previously used as service addresses, but only under certain conditions. The cleanest solution is to use an accountant's or registered-office service address from day one.
Not registering for Corporation Tax within 3 months.HMRC requires registration within three months of the date the company starts trading — not the date of incorporation. The two dates can differ. Failing to register on time attracts a penalty, and HMRC will still expect the tax.
Treating the company as a personal wallet. A limited company is a separate legal person. Money flows out by salary, dividend, or documented expense reimbursement — never as informal transfers. Using the company account to pay personal bills erodes the limited-liability protection and creates serious accounting problems.
No shareholder agreement. Companies House Articles govern the company's formal structure, but they do not cover everything two or more co-founders should agree on: decision-making rights, leaver provisions, dividend policy, exit rights. A short shareholder agreement drafted before trading begins is one of the highest-value documents a multi-founder company can have.
For founders weighing whether a limited company is right for them at all, the comparison with sole-trader status is covered in the limited company vs sole trader guide. And for what happens once you are registered for VAT, see the VAT registration threshold guide.
The full Rajoka starting a business guides cover company formation, funding, compliance, and early-stage operations in depth.
Frequently asked questions
How much does it cost to set up a limited company in the UK?
Registering directly with Companies House costs £50 online or £71 for the same-day service, per GOV.UK. Software-filing via an authorised agent costs £12 in Companies House fees, with the agent adding their own charge. Third-party formation agents typically bundle additional services and charge £30–£150 in total.
How long does it take to register a limited company?
The standard online service processes most applications within 24 hours and often within a few working hours. The same-day service (£71, per GOV.UK) guarantees incorporation on the same working day if submitted before 3pm. Postal applications take 8–10 working days and are rarely used.
Do I need to register for Corporation Tax immediately after incorporating?
You must register with HMRC for Corporation Tax within 3 months of the date the company starts trading, per GOV.UK. This is separate from the Companies House incorporation. Do it via the company's Government Gateway account as soon as you begin any trading activity.
Can I be the sole director and sole shareholder of a UK limited company?
Yes. A UK limited company can have a single director who is also the sole shareholder and the sole Person with Significant Control (PSC). This is the standard setup for solo founders. There is no requirement for a company secretary or additional directors.
What is the difference between a limited company and a sole trader in the UK?
A limited company is a separate legal entity — its debts are the company's, not yours personally. A sole trader has no legal separation, so personal assets are at risk from business debts. Limited companies also pay Corporation Tax (19%–25% per HMRC) rather than Income Tax, which becomes more efficient as profits grow.