Business Registration
for startups

Setting up your startup correctly from day one is crucial for maximising tax reliefs and avoiding costly restructuring later. Entrepreneurs need expert guidance on choosing the right business structure, whether that's a limited company for investor readiness, a partnership for collaborative ventures, or remaining as a sole trader while testing market viability.

The business registration process involves multiple decisions that affect your long-term tax position. From choosing an appropriate SIC code that aligns with potential R&D tax credit claims, to structuring share capital for future SEIS or EIS investment, each choice has implications for your startup's financial future.

Accountants in our network understand the specific challenges facing early-stage businesses, from navigating initial compliance requirements to ensuring your structure supports your growth ambitions whilst minimising administrative burden during critical early trading months.

UK business registration is, on the surface, the simplest decision a founder makes. The Companies House online incorporation portal accepts a name, a registered office, director details, share capital allocations, and a £12 filing fee, and issues a certificate of incorporation typically within 24 hours. Behind that mechanical step sit a dozen choices that lock in tax treatment, investor optionality, and personal liability for the next decade of the business. The decision worth investing time in is not whether to incorporate but how to structure the incorporation so the choices you make on day one don't have to be reversed at higher cost in year two or three.

The first call is the legal structure. UK founders choose between operating as a sole trader (unincorporated, personal income tax on all profits, unlimited personal liability), a traditional partnership (similar tax treatment shared between partners, joint liability), a limited liability partnership (limited liability with partnership tax treatment), and a limited company (corporation tax on profits, dividend treatment for distributions, limited personal liability and access to SEIS, EIS, R&D credits, and EMI). For startups that intend to raise external investment, claim R&D tax credits, or grant equity to early employees, the limited company is effectively the only viable choice because every UK startup tax relief is conditioned on issuing shares from a UK Companies House registered company. Sole trader status is appropriate for genuine freelance work and side ventures but cannot be retrofitted into an investment-receiving structure without an incorporation event that wipes out a portion of pre-incorporation goodwill on the way through.

The second call is the share structure. Companies House requires each company to have at least one share, but in practice founders need to think through the cap table from the start. The standard pattern for a UK startup expecting to raise SEIS investment is to issue founder shares as ordinary shares at nominal value (typically 0.01 pence per share, with a few thousand shares total) at incorporation. This locks in the lowest possible base cost for capital gains tax on eventual exit, lets the cap table be expressed in clean percentages, and leaves room for SEIS investors to receive shares at meaningful prices later without diluting founders into immateriality. Articles of Association should be drafted with pre-emption rights, drag-along and tag-along provisions, and the standard SEIS-compatible language. Many founders use the default Companies House model articles and discover six months in that the articles don't permit the share-class structure their lead investor requires, forcing a special resolution to amend.

The third call is HMRC registration. Incorporation with Companies House triggers automatic registration for corporation tax, with an HMRC notice posted to the registered office within a few weeks. PAYE registration is a separate step required if you'll have employees (including the founder taking salary). VAT registration is mandatory once taxable turnover exceeds £90,000 in any rolling 12-month period (raised from £85,000 in April 2024) and voluntary below. The choice to register for VAT voluntarily depends on whether the company will reclaim more input VAT (on equipment, software, professional fees) than it adds to its consumer-facing prices. For B2B startups serving VAT-registered customers, voluntary early VAT registration is usually a clear win; for direct-to-consumer startups it adds 20% to prices the customer can't reclaim and is often deferred until mandatory.

The fourth call is the SIC code, the standard industry classification that Companies House records and HMRC uses for risk profiling. SIC codes have no direct tax effect but they do affect HMRC enquiry probability. A software company classified under '62012 Business and domestic software development' fits the expected profile for R&D tax credit claims; the same company classified under '70229 Management consultancy activities other than financial management' will look anomalous when a six-figure R&D claim arrives, and HMRC's R&D enquiry team is much more likely to open a check. Choose the SIC code that genuinely describes the activity and matches the relief profile the company will use.

The final consideration is the registered office address. Using the founder's home address is permitted and free, but the address goes on the public Companies House register where it appears in search results and is used for service of legal documents. Many founders opt for the accountant's business address as the registered office, which provides privacy and ensures statutory mail is opened by someone who knows what to do with it. The cost is typically £50-150 per year as part of an accountancy engagement.

Sole trader to limited company incorporations partway through a tax year carry specific complications. The unincorporated trade has to file a final self-assessment up to the cessation date, with closing-year assessment rules applying. Goodwill on incorporation can sometimes be claimed as an intangible asset on the new company's balance sheet, but the rules tightened materially in 2015. Internally generated goodwill (the kind almost every freelancer creates organically) is restricted from amortisation deduction. Externally acquired goodwill can be amortised but the tax rules carve out specific situations. For most freelancer-to-Ltd transitions, the goodwill question is more about getting the figure right for accounting purposes than expecting a real tax saving. The transition itself works mechanically, but the timing and the closing-year-assessment treatment need an accountant who's done it before.

International founders setting up a UK limited company face a banking bottleneck that catches almost everyone. Companies House incorporation accepts non-UK-resident directors without restriction. The UK banking sector almost universally requires either a UK-resident director or a UK-resident beneficial owner to open a business bank account. Founders incorporating from outside the UK typically discover this at week three when they've completed Companies House but can't open Barclays, NatWest, HSBC, or Lloyds business accounts. The workarounds are: appoint a UK-resident co-director or nominee, use a UK-friendly fintech (Wise Business, Revolut Business, Tide) that has more flexible KYC for international founders, or relocate one of the founders to the UK on a visa that permits company directorship. The accountant should flag this constraint on day one of the engagement, not week three.

Multi-founder cap tables need a Shareholders' Agreement, which sits alongside the Articles of Association. Articles are public, filed at Companies House, and govern the company's relationship with its shareholders. The Shareholders' Agreement is private, between the shareholders, and governs their relationship with each other - covering vesting, leaver provisions (good leaver vs bad leaver share buyback rights), pre-emption on share issues, drag-along and tag-along, reserved matters requiring board or shareholder consent, and information rights. The accountant doesn't draft the Shareholders' Agreement (that's a corporate solicitor's job), but the share structure designed at incorporation has to be compatible with a typical investor-friendly Shareholders' Agreement. Designing the cap table without thinking through these provisions leads to expensive restructuring at the first investment round.

EIS, SEIS and EMI all have eligibility tests that depend on conditions met at the company level over various qualifying periods. Some of these conditions can only be controlled by structural choices made at incorporation. SEIS requires the company to be under three years old at the time SEIS shares are issued (counted from the start of trading or the date of incorporation, whichever is later). EIS has a seven-year age limit for the company's first EIS investment. EMI requires the company to be carrying out a qualifying trade at the time options are granted. R&D tax credits require the qualifying trade to be conducted by a UK-resident company with appropriate intellectual property arrangements. All of these tests can be inadvertently broken by structural choices made for non-tax reasons (creating non-trading subsidiaries, intercompany financing arrangements, IP licensing structures), and the loss of any one relief at the wrong moment can mean a substantial tax cost. Building incorporation around the relief stack the company is most likely to use is cheaper and safer than retrofitting.