UK Small Business Finance Guide 2026/27

Choosing a Business Structure

Almost every small business starts as one of three structures: sole trader, partnership, or limited company. A sole trader is the simplest — you register for Self Assessment, trade under your own name or a business name, and are personally liable for any business debts. A partnership works the same way but is shared between two or more people. A limited company is a separate legal entity from its owners, which means the company itself owns the assets and owes the debts, giving the directors and shareholders limited liability protection.

The trade-off is administration and tax. A sole trader has one tax return and pays Income Tax and Class 4 National Insurance on all profits. A limited company must file a Company Tax Return, annual accounts and a confirmation statement with Companies House, and the director typically draws a combination of salary and dividends rather than simply taking profit. See our sole trader vs limited company guide for a full breakdown of when incorporating starts to save tax.

Core Tax Obligations

• Income Tax / Corporation Tax: sole traders and partners pay Income Tax on profits through Self Assessment; limited companies pay Corporation Tax at 19% (profits up to £50,000), 25% (above £250,000), or a tapered marginal rate in between
• National Insurance: sole traders pay Class 4 NI on profits above the lower profits limit; company directors pay Class 1 NI on salary, and the company pays Employer NI
• VAT: registration is compulsory once taxable turnover exceeds £90,000 in a rolling 12-month period, with quarterly returns the norm
• PAYE: required once you employ any staff (including yourself as a company director drawing a salary), covering Income Tax and NI deducted at source

Cash Flow Planning

Profit and cash are not the same thing, and the gap between them is where most small business failures happen. A business can be profitable on paper while running out of cash because customers pay late, stock has to be bought before it is sold, or a large tax bill falls due at an inconvenient time.

• Keep a rolling 13-week cash flow forecast, updated weekly, rather than relying on the profit and loss account alone
• Set aside a fixed percentage of every payment received — commonly 20-30% — into a separate account earmarked for VAT and tax, so it is never spent by accident
• Invoice promptly and chase overdue invoices systematically; late payment from customers is the most common cause of a cash squeeze
• Build a cash buffer of at least one to three months of operating costs where possible

Funding Options

Beyond a standard bank loan, small businesses have several funding routes, each suited to a different need:

• Overdraft / revolving credit: for short-term working capital gaps
• Invoice finance: releases cash tied up in unpaid customer invoices, useful for B2B businesses with long payment terms
• Asset finance: spreads the cost of equipment or vehicles rather than paying up front
• Start Up Loans: a government-backed personal loan scheme for new and early-stage businesses, alongside free mentoring
• Equity investment: angel investors or venture capital, exchanging a share of ownership for growth capital, usually only suitable for high-growth ambitions

Key Deadlines

• Self Assessment online filing and balancing payment: 31 January following the tax year end
• Self Assessment second payment on account (where applicable): 31 July
• Company Tax Return: within 12 months of the accounting period end
• Corporation Tax payment: 9 months and 1 day after the accounting period end
• VAT returns and payment: usually 1 month and 7 days after each quarterly period end
• Companies House confirmation statement and annual accounts: within set windows after the company's year end and anniversary of incorporation

Worked Example

Priya runs a graphic design business and expects profits of £45,000 in 2026/27. As a sole trader, she pays Income Tax and Class 4 National Insurance on the full £45,000 through Self Assessment. She sets aside 25% of every invoice into a separate savings account, so when her 31 January bill arrives she already has the cash ready rather than scrambling to find it.

As her turnover approaches £90,000, she registers for VAT in good time rather than waiting for the threshold to be breached, since a late registration can trigger backdated VAT liabilities and penalties. She also models incorporating as a limited company once her profits look likely to exceed around £40,000 consistently, using CalcHub's corporation tax and salary calculators to compare her after-tax income under both structures before deciding.

Common Pitfalls

• Spending the VAT and tax money. Treating everything in the business account as available cash is the single most common cause of a painful tax bill shortfall.
• Registering for VAT late. Missing the 30-day registration window after crossing the £90,000 threshold can lead to backdated VAT owed on sales where you never charged it.
• Incorporating too early, or too late. Incorporating before profits justify it adds unnecessary admin; delaying too long after profits rise can mean paying more Income Tax and NI than a limited company structure would.
• No cash flow forecast. Relying on the bank balance alone, rather than a forward-looking forecast, means cash gaps are only spotted once they have already arrived.
• Mixing personal and business finances. Not having a dedicated business account makes bookkeeping error-prone and slows down every tax return and funding application.