Expense Tracking

Expense tracking is the process of recording, categorising and monitoring every cost your business incurs. Done well, it ensures you claim every allowable deduction on your tax return, keeps your cash flow visible and gives HMRC exactly what they need if they enquire into your records.

Done badly – or not at all – it means you pay more tax than necessary, lose sight of where your money goes and risk penalties for incomplete records.

Why expense tracking matters

There are three core reasons to track expenses properly:

1. Tax relief – every legitimate business expense reduces your taxable profit, lowering your Corporation Tax or Income Tax bill
2. Cash flow visibility – knowing what you spend and where helps you make better decisions
3. Legal compliance – HMRC requires you to keep records of all business expenditure

For sole traders, allowable expenses reduce your profit on your Self Assessment return. For limited companies, they reduce the profit on which you pay Corporation Tax at 19-25%.

What counts as an allowable expense

HMRC’s rule is that an expense must be incurred wholly and exclusively for business purposes. If something has a dual purpose (partly personal, partly business), you can claim only the business proportion.

Common allowable expenses

Expenses you cannot claim

• Personal expenses – groceries, personal clothing, gym memberships
• Client entertaining – meals and hospitality for clients (deductible for accounting but not for tax)
• Fines and penalties – parking tickets, HMRC penalties, court fines
• Political donations
• Capital expenditure – the purchase price of assets (but capital allowances apply separately)

Tracking methods

Spreadsheet

A spreadsheet works for very small businesses with few transactions. Set up columns for date, supplier, description, amount, VAT, category and payment method. The downside is that everything is manual, and it is easy to miss entries or make formula errors.

Accounting software

Modern accounting software automates most of the expense tracking process:

• Bank feeds import transactions directly from your bank account
• Receipt scanning captures expense data from a photograph
• Rules and patterns learn to categorise recurring expenses automatically
• VAT codes are applied based on the supplier and expense type
• Reports show spending by category, period or project in real time

This is significantly more efficient and accurate than manual methods, especially as your transaction volume grows.

Dedicated expense apps

If you or your employees regularly incur expenses on the go, a mobile app that integrates with your accounting software is the most practical approach. Photograph the receipt, categorise the expense and submit it for approval – all from your phone.

Home office expenses

If you work from home, you can claim a proportion of your household costs. There are two methods:

Simplified method (HMRC flat rate)

This is easy to calculate but typically gives a lower deduction.

Actual cost method

Calculate the proportion of your home used for business (based on rooms or floor area) and claim that percentage of:

• Rent or mortgage interest
• Council tax
• Electricity, gas and water
• Home insurance
• Broadband (business proportion)

The actual cost method usually gives a larger deduction if you have a dedicated workspace, but requires more record-keeping.

Mileage and vehicle expenses

If you use a personal vehicle for business, you can claim the HMRC approved mileage rates:

Keep a mileage log with the date, start and end points, purpose and distance for each business journey. Commuting does not count as business travel.

Alternatively, you can claim the actual running costs (fuel, insurance, servicing, road tax) based on the business proportion of total miles driven. Once you choose a method for a vehicle, you must stick with it.

Employee expenses

If your business has staff, you need a clear system for employee expense claims:

1. Define an expense policy – what can be claimed, spending limits, approval process
2. Require receipts for all claims over a set threshold
3. Set submission deadlines – monthly or per pay period
4. Review and approve before reimbursing
5. Record in your accounts – each reimbursement must be coded to the correct expense category

Expenses reimbursed to employees are generally tax-free for the employee and deductible for the business, provided they meet HMRC’s “wholly and exclusively” test.

VAT on expenses

If you are VAT-registered, you can reclaim the input VAT on most business expenses. To do this, you need a valid VAT invoice or receipt showing the supplier’s VAT registration number.

Some expenses have restricted VAT treatment:

Monthly expense review

Set aside time each month to:

• Reconcile all bank and credit card transactions against receipts
• Check for missing receipts and request duplicates from suppliers
• Review categories to ensure expenses are coded correctly
• Identify unusual spending that might indicate errors or overspending
• Update your cash flow forecast based on actual spending patterns

This takes 30 minutes to an hour for most small businesses and saves considerable time at year end.

Common expense tracking mistakes

• Not recording small purchases – petty cash items add up to meaningful deductions over a year
• Claiming disallowed expenses – client entertaining is the most common; it is not tax-deductible even though it is a real business cost
• Missing the VAT element – forgetting to separate and reclaim input VAT on eligible purchases
• Inconsistent categorisation – coding the same type of expense to different accounts makes reporting unreliable
• Year-end scramble – trying to reconstruct a year of expenses from bank statements alone is slow and error-prone

The simplest fix for all of these is to record expenses as they happen, not weeks or months later. Emailing each receipt to accounting software that reads it for you as soon as you pay makes this near-automatic.