Allowable business expenditure

Managing your business expenses effectively is key to reducing your tax bill and maintaining accurate financial records. In the UK, HMRC allows businesses to deduct certain costs – known as allowable expenditure – from their income before calculating taxable profit.

Understanding what qualifies (and what doesn’t) ensures you’re not overpaying tax while staying compliant.

What Is allowable expenditure?

Allowable expenditure refers to costs that are wholly and exclusively incurred for the purposes of running your business. These expenses can be deducted from your revenue, reducing the amount of profit on which you pay tax.

This applies whether you operate as a sole trader or a limited company, although the way expenses are recorded and reported may differ slightly.

Common types of allowable expenses

Most businesses will incur a range of day-to-day costs that are typically allowable, including:

• Office and running costs: expenses such as rent, utilities, office supplies, software subscriptions, and internet costs are generally allowable, provided they relate to business use.
• Travel and transport: you can claim for business-related travel, including fuel, train fares, parking, and vehicle running costs. However, commuting between home and a regular workplace is not allowable.
• Professional fees: accountancy, legal advice, and other professional services directly related to running your business are fully deductible.
• Staff costs: salaries, wages, bonuses, pensions, and employer National Insurance contributions are all allowable expenses for limited companies.
• Marketing and advertising: costs for promoting your business; such as online advertising, or branding; are typically allowable.
• Insurance: business-related insurance policies, such as public liability or professional indemnity, can be claimed.

Expenses with mixed use

Some costs may have both business and personal elements. In these cases, you can only claim the business proportion.

For example:

• Using your home as an office: claim a reasonable portion of utilities or use HMRC’s simplified flat-rate method
• Mobile phone bills: claim only the business usage

Keeping clear records to support how you apportion these costs is essential.

Capital vs revenue expenditure

Not all spending is treated the same way. It’s important to distinguish between:

• Revenue expenditure: day-to-day running costs (fully deductible in the year incurred)
• Capital expenditure: larger purchases such as equipment, machinery, or vehicles

Capital items are not deducted in the same way, but you may be able to claim capital allowances (including the Annual Investment Allowance) to reduce taxable profits.

Non-allowable expenses

Some costs are specifically disallowed by HMRC or restricted, including:

• Personal expenses not related to the business
• Client entertainment (e.g. meals, hospitality)
• Fines, penalties, or parking tickets
• Drawings (for sole traders) or dividends (for company directors)

Understanding these distinctions is important to avoid errors and potential HMRC challenges.

Keeping accurate records

To claim expenses confidently, you should maintain records of:

• Receipts and invoices
• Bank statements
• Clear notes for any mixed-use costs

Digital record-keeping tools, such as Xero, are recommended as they can make this process much simpler and ensure you’re prepared in the event of a review. They also track the performance of the business in real time.

Why it matters

Claiming all eligible expenses can significantly reduce your tax liability. Equally, incorrectly claiming costs can lead to penalties.

A proactive approach to managing allowable expenditure helps you:

• Improve cash flow
• Stay compliant with HMRC
• Make better-informed business decisions

Getting it right

While many expenses are straightforward, some areas – such as travel, home office use, and capital purchases – require careful judgement.

Taking professional advice can ensure you maximise your claims while remaining fully compliant, giving you confidence that your business finances are handled correctly.