Small Business Accounting: A Simple UK Guide for 2026

Small business accounting is the process of tracking your income, expenses, taxes, and financial records to stay compliant with HMRC and manage your business finances.

But keeping on top of your finances doesn’t need to be complicated. 

Here's what you need to know about small business accounting in the UK, including how to choose the right structure, what to file, when to file it, and how to avoid common mistakes. 

Key points

• Keep business and personal finances separate 💳
  Using a dedicated business account makes it easier to track expenses and income, claim allowable expenses, prepare tax returns, and maintain accurate records to present to HMRC as evidence.
• Choose the right business structure 🏢
  Whether you're a sole trader, partnership, or limited company affects how you're taxed, what you need to file, and how you can take money out of the business. Understanding your structure from the start can help you avoid costly mistakes later.
• Stay on top of bookkeeping and Making Tax Digital (MTD) 📊
  Keeping accurate records throughout the year makes accounting much simpler and prepares your business for MTD requirements. Digital bookkeeping can also save time and reduce the risk of errors.
• Claim every allowable expense you're entitled to 💷
  Business expenses reduce your taxable profit, which means you pay less tax. Common claims include office costs, travel, software subscriptions, professional fees, and working-from-home expenses.
• Use tools that simplify accounting and tax admin 🚀
  Managing bookkeeping is much easier when everything works together. ANNA combines accounting and cash management in one place, helping small business owners spend less time on admin and more time growing their business.

The first step: Separate your business finances

Before thinking about tax returns or choosing accounting software, make sure your business finances are separate from your personal spending.

This makes it easier to:

• Track income and expenses
• Prepare VAT returns
• Claim business expenses
• Demonstrate accurate records to HMRC

Many business owners choose a dedicated business bank account even when they're not legally required to have one.

💡 Did you know?

ANNA’s business account helps you keep business and personal finances separate from day one. You can track income and expenses, capture receipts, send invoices, and manage your bookkeeping from a single place, so it’s easy to stay organised. 

Understand the basics: Your business structure

Your legal structure determines how you're taxed, how you take money from the business, and what records you need to keep. 

There are three main business structures in the UK:

Sole trader

As a sole trader, you and your business are legally the same entity. You report income and expenses through a Self Assessment tax return each year. 

It’s the simplest structure to set up and run, but you’re personally liable for any debts the business takes on.

Partnership

A partnership works similarly to sole trading, except profits are shared between two or more people. Each partner files their own Self Assessment return and reports their share of the income. You will also need to file a Partnership Tax Return (SA800) each year.

Limited company

A limited company is a separate legal entity from its owners. It pays Corporation Tax on its profits, and directors typically take a mix of salary and dividends. 

The accounting is more involved: you'll need to file annual accounts with Companies House and a Corporation Tax return with HMRC.

Set up your bookkeeping

Bookkeeping is the process of recording every penny that comes in and goes out of your business. If done consistently, it makes tax time straightforward. But if done poorly or not at all, it can lead to mistakes, missed deductions, and HMRC enquiries.

What you need to track

Make sure you keep records of:

• All income, including sales, invoices, and any other money your business receives
• All business expenses, with receipts or invoices to back them up
• VAT, if you’re registered
• Payroll, if you have employees
• Any assets you purchase for the business

You can track financial activities using HMRC-recognised accounting software, a bookkeeping service, or bridging software if you prefer spreadsheets. 

The new way: Making Tax Digital

Making Tax Digital (MTD) is HMRC's long-term plan to move tax reporting away from manual, paper-based processes toward digital record-keeping and online submissions.

Making Tax Digital for VAT (MTD for VAT)

MTD for VAT is already in place. If you're VAT registered, you must keep digital records and submit VAT returns using compatible software.

Making Tax Digital for Income Tax Self Assessment (MTD for ITSA)

Instead of relying solely on a yearly tax return, sole traders and landlords will need to keep digital records and send quarterly income and expense updates to HMRC using compatible software, followed by a final end-of-year declaration.

MTD for ITSA is being introduced in stages based on qualifying income:

• From April 2026: qualifying income above £50,000
• From April 2027: qualifying income above £30,000
• From April 2028: qualifying income above £20,000

🧠 Good to know

MTD for ITSA will eventually apply to almost every sole trader and landlord, so even if you’re not there yet, switching to digital bookkeeping now can make the transition to MTD significantly easier. 

Tax obligations and deadlines

Your tax responsibilities will vary according to your business structure, VAT status, and employment status as a business owner. 

For most small businesses, the main taxes are:

• Income Tax and National Insurance (for sole traders and partnerships)
• Corporation Tax (for limited companies)
• Dividend Tax (for company directors taking dividends)
• VAT (if you're registered)
• PAYE and employer National Insurance (if you have employees)

Income Tax and National Insurance

If you’re a sole trader or in a partnership, you’ll pay Income Tax on your business profits through Self Assessment, along with Class 4 NIC. 

Here are the 2026/27 rates for Income Tax and NIC:

The Personal Allowance and basic rate threshold are frozen until April 2028. As your income grows, you may find yourself moving into a higher band even if the rates themselves haven’t changed.

Corporation Tax and Dividend Tax

If you run your business through a limited company, you'll usually pay tax in two stages. First, the company pays Corporation Tax on its profits.

Then, if you take money out of the company as dividends, you may pay Dividend Tax personally.

The amount of tax you pay depends on the company's profit and the dividend income you receive.

VAT

VAT registration becomes compulsory once your taxable turnover exceeds £90,000 in any 12-month period. 

You can also register voluntarily below the VAT registration threshold. This can make sense if your customers are VAT-registered businesses, since you can reclaim VAT on your own purchases.

The VAT rates for 2026/27 are:

Once registered, you’ll file VAT returns every quarter and pay any VAT owed within one month and seven days of the end of each quarter. You have to do this digitally through MTD software.

💡 Did you know? 

ANNA is HMRC-recognised for MTD for VAT, allowing eligible businesses to keep digital records and submit VAT returns in line with all digital requirements. 

Payroll and employing staff

Hiring employees comes with extra admin and tax responsibilities. Before you pay anyone, you'll need to register as an employer with HMRC and set up a payroll system.

If you employ staff, you'll also need to:

• Run PAYE (Pay As You Earn), the system used to collect Income Tax and National Insurance from employees' wages
• Pay employer NICs in addition to the employee's salary
• Enrol eligible employees into a workplace pension scheme under the auto-enrolment rules
• Send payroll information to HMRC each payday using a Full Payment Submission (FPS) 

For the 2026/27 tax year, Employer NICs are charged at 15% on an employee's earnings above £5,000 per year.

🧠 Good to know

Many small businesses can reduce their employer National Insurance bill through the Employment Allowance. If you’re eligible, you may be able to cut your insurance costs by up to £10,500 per year.

Self Assessment: What to file and when

If you’re a sole trader, partner, or company director, you’ll likely need to file a Self Assessment tax return each year.

A Self Assessment return is how you report your income to HMRC and work out how much tax you need to pay. 

Here are the Self Assessment deadlines for 2026/27:

Payments on account are advance payments towards the following year's tax bill, calculated as 50% of your previous year's bill. 

🧠 Good to know 

ANNA can prepare and file your Self Assessment for free. Even if you’ve already paid another provider, ANNA will refund the filing fee when you switch.

Small business accounting: Claiming allowable expenses

Claiming allowable expenses can reduce your tax bill by lowering your taxable profit.

As a general rule, an expense must be wholly and exclusively for business purposes to be tax-deductible.

Common allowable expenses include:

• Office costs, such as stationery, printer ink, phone bills, and software subscriptions
• Business travel, including train fares, fuel costs, parking, and accommodation for work trips
• Staff costs, including wages, subcontractor payments, and employer pension contributions
• Professional services, such as accountancy, legal, and insurance costs
• Marketing and advertising, including website costs, online advertising, and promotional materials
• Training courses that help you maintain or improve skills used in your existing business
• Protective clothing and uniforms required for your work

Keeping receipts and accurate records throughout the year makes it easy to support your claims if HMRC ever asks for evidence.

Capital allowances

If you buy equipment, machinery, tools, or other assets that will last for several years, you may not be able to claim them as a standard business expense.

Instead, you can usually claim tax relief through capital allowances. The Annual Investment Allowance (AIA) currently allows most businesses to deduct the full cost of qualifying plant and machinery, up to £1 million per year, in the year of purchase.

Working from home

If you run your business from home, you may also be able to claim some of your household costs as a business expense.

HMRC offers a simplified flat-rate method based on the number of hours you work from home each month:

Alternatively, you can calculate the actual business proportion of your household costs, which may result in a larger deduction, but requires more detailed record-keeping.

For example, if your home office occupies 20% of your home's space and is used full-time for business, you may be able to claim 20% of your overall household bills as business expenses. Adjustments may be needed if the room is also used for personal purposes. 

How ANNA can help with small business accounting

Managing your accounts is easier when your cash flow, bookkeeping, and tax tools work together. 

ANNA combines all of them into a single platform, helping you spend less time on admin and more time running your business.

Here’s what ANNA has to offer:

• Smart business account: Keep your personal and business finances separate
• Auto Accountant: Categorise transactions automatically and keep your bookkeeping organised
• Receipt scanner: Store receipts digitally and match them to transactions for easier expense tracking
• Seamless invoicing: Create, send, and track professional invoices from one place
• VAT filing: Submit MTD-compatible VAT returns directly to HMRC
• Free Self Assessment filing: Submit your Self Assessment tax return without additional filing fees
• Payroll: Manage employee payroll and stay on top of reporting requirements

Sign up with ANNA today and simplify your bookkeeping.