Setting up a business in the UK is more straightforward than many people expect — but getting the structure right from the start matters enormously. The decisions you make in the first few weeks will affect how you pay tax, what your legal liabilities are, how you can raise investment, and how your business is perceived by clients and suppliers. This guide walks you through every step, from choosing your business structure to completing your first year of compliance obligations.
The good news is that the UK has one of the most business-friendly registration environments in the world. You can register a limited company online in under 24 hours for a modest fee, and the process is well-documented by GOV.UK. The challenge is not the registration itself — it is making the right choices before you register.
Before registering your business, you should have a clear business idea, a basic business plan, and a sense of your expected income in the first year. These will help you choose the right structure and avoid costly changes later. If you are unsure, a one-hour session with a business adviser can save you significant time and money.
Choosing Your Business Structure
The most important decision you will make when setting up is your business structure. In the UK, the four main options are sole trader, limited company, business partnership, and limited liability partnership (LLP). Each has different implications for tax, legal liability, administration, and credibility. The vast majority of new UK businesses choose between sole trader and limited company.
Sole Trader
SimplestThe simplest way to trade. You and the business are legally the same entity. You keep all profits after tax, but you are personally liable for all business debts.
✓ Pros
- Free to set up
- Minimal admin
- Simple tax returns
- Full control
✗ Cons
- Personal liability
- Harder to raise investment
- Less tax efficient at higher profits
- Less credible to some clients
Limited Company
Most PopularA separate legal entity from its owners. Shareholders' liability is limited to the value of their shares. More complex to administer but more tax-efficient at higher profit levels.
✓ Pros
- Limited liability protection
- Tax-efficient at higher profits
- Easier to raise investment
- More credible to larger clients
✗ Cons
- More admin & compliance
- Annual accounts filing required
- Public record of directors
- More complex tax planning
Business Partnership
2+ PeopleTwo or more people sharing profits, losses, and management of a business. Each partner is personally liable for the partnership's debts, including those incurred by other partners.
✓ Pros
- Simple to set up
- Shared responsibility
- Flexible profit sharing
✗ Cons
- Joint & several liability
- Disputes can be complex
- No limited liability
Limited Liability Partnership
Professional FirmsCombines the flexibility of a partnership with the limited liability of a company. Popular with professional services firms such as solicitors and accountants.
✓ Pros
- Limited liability
- Flexible management
- Tax transparency
✗ Cons
- More complex than partnership
- Public accounts filing
- Less common — less understood
Sole Trader vs Limited Company: The Key Differences
For most new UK business owners, the decision comes down to sole trader versus limited company. The table below summarises the key differences based on official GOV.UK guidance.
| Factor | Sole Trader | Limited Company |
|---|---|---|
| Legal liability | Unlimited — personal assets at risk | Limited to the value of your shares |
| Registration | Register for Self Assessment with HMRC | Register with Companies House (£50 online) |
| Tax on profits | Income Tax (20%–45%) + Class 4 NI | Corporation Tax on company profits |
| Taking money out | Keep all profits after tax | Salary + dividends (tax planning required) |
| Annual admin | Self Assessment tax return | Accounts, Confirmation Statement, CT600 |
| Privacy | No public record required | Directors & accounts on public register |
| Raising investment | Difficult — no shares to issue | Can issue shares to investors |
| Credibility | Sufficient for most small businesses | Often preferred by larger clients & corporates |
| Accountancy costs | Lower — simpler accounts | Higher — more complex compliance |
A limited company typically becomes more tax-efficient than sole trader status when your annual profits consistently exceed approximately £30,000–£40,000. Below this level, the additional accountancy costs of running a limited company may outweigh the tax savings. The right threshold depends on your personal circumstances — always take professional tax advice before deciding.
How to Register a Limited Company
If you have decided that a limited company is the right structure for you, the registration process is straightforward. You can register online via the Companies House web incorporation service or through a company formation agent. Here is the step-by-step process.
Choose Your Company Name
Your company name must be unique and not too similar to an existing registered company. It must end in "Limited" or "Ltd". Check availability on the Companies House register before proceeding. You can also trade under a different trading name.
Choose a Registered Address
Every limited company must have a registered address in the UK — this is the official address for legal correspondence and will appear on the public register. It can be your home address, your accountant's address, or a registered office service address.
Appoint Directors
You must appoint at least one director. Directors are legally responsible for running the company and filing statutory documents. You can be the sole director and shareholder. Directors must be at least 16 years old and not disqualified from acting as a director.
Decide on Shareholders & Share Structure
You must issue at least one share. For a simple owner-managed company, issuing 100 ordinary shares of £1 each is a common starting point. If you have co-founders or plan to bring in investors, take advice on your share structure before registering.
Prepare Your Articles of Association
The Articles of Association are the rules governing how your company is run. For most small companies, the standard "Model Articles" provided by Companies House are perfectly adequate. You can adopt these without any modification.
Identify People with Significant Control (PSC)
You must identify any individuals who own more than 25% of shares, have more than 25% of voting rights, or otherwise have significant control over the company. This information is recorded on the PSC register, which is publicly accessible.
Register Online with Companies House
Complete the IN01 form online at Companies House. You will need all the information from the steps above. The fee is £50 for standard registration (24–48 hours) or £78 for same-day registration. You will receive a Certificate of Incorporation by email.
Register for Corporation Tax with HMRC
Within three months of starting to trade, you must register your company for Corporation Tax with HMRC. You can do this online via your HMRC business tax account. HMRC will send you a Unique Taxpayer Reference (UTR) for your company.
Not Sure Which Structure Is Right for You?
Our advisers can help you choose the right business structure, understand the tax implications, and get set up correctly from day one.
How to Register as a Sole Trader
Registering as a sole trader is simpler than forming a limited company. You do not need to register with Companies House — you simply need to register for Self Assessment with HMRC. You must do this by 5 October in your second year of trading (i.e., by 5 October following the end of the first tax year in which you earned more than £1,000 from self-employment).
Register for Self Assessment
Register online at GOV.UK. You will need your National Insurance number and personal details. HMRC will send you a UTR (Unique Taxpayer Reference) within 10 working days.
Set Up a Government Gateway Account
You will need a Government Gateway account to manage your tax affairs online. If you do not already have one, create one during the registration process.
Keep Records from Day One
You are legally required to keep records of all your income and expenses. Use accounting software or a simple spreadsheet. You will need these records to complete your Self Assessment tax return each year.
Submit Your Tax Return Annually
Your Self Assessment tax return covers the tax year (6 April to 5 April). The deadline for online submission is 31 January following the end of the tax year. Pay any tax owed by the same date.
Startup Funding & Finance Options
Once your company is registered, you may need funding to get started. Our startup funding guide covers grants, loans, angel investment, and more.
Your HMRC Obligations After Registration
Registering your company is just the beginning. Once you are trading, you will have ongoing obligations to HMRC. Understanding these from the start will help you avoid penalties and keep your finances in order.
| Obligation | Who It Applies To | Deadline / Frequency | Notes |
|---|---|---|---|
| Corporation Tax registration | All limited companies | Within 3 months of trading | Register via HMRC business tax account |
| Corporation Tax return (CT600) | All limited companies | 12 months after accounting period end | Tax due 9 months after accounting period end |
| Self Assessment registration | Sole traders; company directors with other income | By 5 October (year 2) | Required if earning over £1,000 self-employed |
| VAT registration | Businesses exceeding the VAT threshold | Within 30 days of exceeding threshold | Can register voluntarily below threshold |
| PAYE registration | Any business employing staff or paying director salary | Before first payday | Register as employer with HMRC |
| Payroll (RTI) | All employers | Each pay period (Real Time Information) | Submit Full Payment Submission on or before payday |
Your Companies House Obligations
Limited companies have ongoing filing obligations with Companies House, separate from their HMRC obligations. Missing these deadlines can result in financial penalties and, ultimately, your company being struck off the register.
Annual Accounts
You must file annual accounts (also called statutory accounts) with Companies House each year. The deadline is 9 months after your company's accounting reference date for private companies. First accounts must be filed within 21 months of incorporation.
Confirmation Statement
You must file a Confirmation Statement at least once every 12 months, confirming that your company's details on the register are up to date. The fee is £34 online. This replaced the old Annual Return in 2016.
Notify Changes Promptly
Any changes to your company's details — new directors, change of registered address, share transfers, changes to the PSC register — must be notified to Companies House promptly, usually within 14 days.
Keep Statutory Registers
You must maintain statutory registers including the register of members, register of directors, register of PSCs, and register of charges. These can be kept at your registered address or at Companies House.
Post-Registration Checklist
Once your company is registered, there are several practical steps to take before you start trading. Use this checklist to make sure you have covered the essentials.
Open a Business Bank Account
Keep business and personal finances completely separate from day one. See our Business Banking guide.
Appoint an Accountant
Engage a qualified accountant early. They will save you more in tax than they cost in fees and keep your compliance on track.
Set Up Accounting Software
Use cloud accounting software (Xero, QuickBooks, FreeAgent) from day one to track income, expenses, and VAT.
Get Business Insurance
Consider professional indemnity, public liability, and employers' liability insurance (legally required if you have employees).
Register for VAT (if applicable)
Register for VAT if you expect to exceed the threshold, or consider voluntary registration if your customers are VAT-registered.
Build Your Website
Establish your online presence. See our Build A Website guide for cost-effective options.
Write a Business Plan
A business plan is not just for funding — it is your roadmap. See our Business Planning guide.
Protect Your Intellectual Property
Consider registering your brand as a trademark with the UK Intellectual Property Office if it is a key business asset.
Register for PAYE (if employing staff)
Register as an employer with HMRC before your first payday if you plan to employ anyone, including yourself as a director.
Set Up Auto-Enrolment (if employing staff)
Employers must automatically enrol eligible workers into a workplace pension scheme. The Pensions Regulator website has full guidance.
Ready to Write Your Business Plan?
A strong business plan is the foundation of a successful business — and essential if you need funding. Our guide walks you through every section.
Common Company Setup Mistakes to Avoid
| Mistake | Why It Happens | How to Avoid It |
|---|---|---|
| Choosing the wrong structure | Defaulting to limited company without considering sole trader | Take advice on your expected income and personal circumstances before deciding |
| Using personal bank account for business | Seems simpler at the start | Open a dedicated business account before your first transaction |
| Missing the Corporation Tax registration deadline | Not knowing the 3-month rule | Register with HMRC within 3 months of starting to trade |
| Poor share structure at incorporation | Not thinking about future investors or co-founders | Take legal advice if you have co-founders or plan to raise investment |
| Not appointing an accountant early enough | Trying to save money at the start | Engage an accountant before you start trading — not at year-end |
| Ignoring VAT registration | Not monitoring turnover against the threshold | Set up a system to track cumulative turnover and register promptly when required |
Frequently Asked Questions
Registering a limited company online with Companies House costs £50 (as of 2025). The same-day registration service costs £78. You can also use a company formation agent, which typically costs between £10 and £100 depending on the service level, and they handle the paperwork on your behalf.
Online registration with Companies House typically takes between 24 and 48 hours. The same-day service, available for an additional fee, can have your company registered within hours. Postal registration takes 8 to 10 working days.
The right choice depends on your circumstances. Sole trader status is simpler, cheaper to maintain, and sufficient for many freelancers and small businesses. A limited company offers limited liability protection, potential tax efficiency at higher profit levels, and often looks more credible to larger clients. Most business advisers suggest considering incorporation when your profits consistently exceed around £30,000–£40,000 per year, though the right threshold depends on your personal tax situation.
You do not legally need an accountant to register a limited company — you can do it yourself online via Companies House. However, engaging an accountant from the start is strongly recommended. They can advise on the most tax-efficient structure, set up your payroll and VAT registration, and ensure your first accounts are filed correctly. The cost of an accountant is typically far less than the tax savings they generate.
You must register for VAT when your taxable turnover exceeds the VAT registration threshold in any rolling 12-month period. You can also register voluntarily below the threshold, which can be advantageous if your customers are VAT-registered businesses and you have significant VAT-able expenses. Check the current threshold on GOV.UK as it is reviewed periodically.
A Confirmation Statement is a yearly filing with Companies House that confirms your company's key details are up to date — including registered address, directors, shareholders, and SIC code. It must be filed at least once every 12 months. The filing fee is £34 online. Failure to file is a criminal offence and can result in your company being struck off the register.