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A business subscription paid from your personal account. Fuel for a client visit. A laptop used for both work and family life. These are ordinary purchases, but treating them incorrectly can mean paying too much tax or claiming relief you are not entitled to.
UK self-employed people can deduct qualifying business expenses such as stock, office costs, business travel, insurance, staff pay, marketing and relevant training when calculating taxable profit. Shared costs must be restricted to their identifiable business element, while equipment may qualify through expenses or capital allowances. You cannot deduct actual expenses against trading income for which you claim the £1,000 trading allowance. HMRC’s allowable expenses guidance
This guide focuses on sole traders, including freelancers, consultants, tradespeople and online sellers. Many principles also apply to partnerships, but limited companies have separate rules.
Use this list to identify potential deductions. The restriction beside each category matters just as much as the example.
Expense category | Examples that may qualify | What to check |
Office supplies | Stationery, postage, printing and ink | Exclude private purchases. |
Software and communications | Business subscriptions, mobile bills and broadband | Apportion shared use; some software purchases need capital treatment. |
Premises and workspace | Office rent, coworking desk hire, rates, utilities and security | Buying or improving premises is different from paying running costs. |
Working from home | A reasonable share of household costs or eligible simplified expenses | Support the calculation and avoid duplicate claims. |
Travel and vehicles | Qualifying mileage, fares, parking and overnight accommodation | Exclude private travel, ordinary commuting and fines. |
Stock and materials | Resale goods, raw materials and production consumables | Exclude private use and apply the correct accounting method. |
Packaging and delivery | Boxes, labels, postage and business courier charges | Retain purchase and delivery records. |
Staff and subcontractors | Wages, employer National Insurance, employer pension contributions and contractor fees | Your own drawings are not wages. |
Work clothing | Protective equipment, genuine uniforms and performers’ costumes | Ordinary clothes remain excluded even if worn only for work. |
Business insurance | Public liability, professional indemnity and business equipment cover | Check what the policy covers; personal cover is not automatically deductible. |
Banking and payment costs | Business account fees, card-processing charges and business borrowing interest | Loan capital repayments are not running expenses. |
Professional services | Bookkeeping, business accounts and qualifying legal advice | Separate personal work and capital transactions. |
Marketing | Advertising, website hosting and promotional printing | Client entertainment is generally excluded; website development may need separate treatment. |
Professional subscriptions | Relevant trade journals and professional memberships | Exclude unrelated personal memberships. |
Training | Relevant technical, administrative and business courses | The course must support the existing business. |
Repairs and equipment | Equipment repairs, tools, computers and machinery | Repairs, replacements and improvements may follow different tax rules. |
Bad debts | Qualifying irrecoverable trading debts | Generally relevant to traditional accounting, not cash basis. |
The main categories follow HMRC’s guidance on office and premises costs, travel, stock, staff, clothing, financial costs, marketing and subscriptions and training.
An allowable trading expense must normally be incurred wholly and exclusively for the business. A receipt confirms a purchase; it does not establish its tax treatment.
Paying privately does not automatically prevent a business deduction. Paying through a business account does not turn personal spending into a business cost.
For a genuinely separable mixed-use expense, claim the identifiable business portion. For example, a £600 annual mobile bill with supportable business use of 70% produces a £420 deduction. Keep the basis of the calculation rather than choosing a convenient percentage.
Some costs have inseparable private and business purposes. A client-meeting suit cannot simply be treated as 80% business because that is how often you wear it professionally. HMRC’s business-purpose test
Allowable expenses reduce taxable profit, not your tax bill pound for pound. If a £500 deduction falls entirely within a 20% Income Tax band, the Income Tax saving is £100. Your overall saving depends on your tax position, including National Insurance and allowances.
For an eligible vehicle, compare simplified mileage with the business proportion of actual costs before choosing a method.
Vehicle and annual business mileage | 2025/26 | 2026/27 |
Cars and goods vehicles: first 10,000 business miles | 45p per mile | 55p per mile |
Cars and goods vehicles: miles above 10,000 | 25p per mile | 25p per mile |
Motorcycles | 24p per mile | 24p per mile |
For 8,000 qualifying car miles in 2026/27, the simplified deduction is £4,400. The equivalent 2025/26 deduction is £3,600.
The mileage rate replaces covered purchase and running costs. Do not add fuel, insurance, servicing or capital allowances for the same vehicle. Qualifying parking and other travel expenses can be separate claims.
You cannot use simplified mileage for a vehicle whose purchase cost you have already deducted or on which you have claimed capital allowances. Once adopted, the method must continue while that vehicle remains in business use. Certain specialist vehicles are excluded. HMRC’s simplified mileage rules
With the actual-cost method, calculate the allowable business share of running costs and consider any separate relief for the vehicle purchase. Keep a mileage record whichever method you use.
Ordinary journeys between home and a regular business base are generally excluded. Travel to changing sites needs assessment against your actual working pattern: departing from home does not itself make a journey deductible.
Hotels and meals on qualifying overnight business trips may be allowable. Everyday lunches are not automatically deductible, and a business discussion over a client meal does not remove the client-entertainment restriction. HMRC’s travel guidance
Self-employed home-working expenses can be calculated using eligible simplified rates or an appropriate share of actual household costs.
Simplified home-working expenses
Business hours worked at home per month | Monthly deduction |
25–50 | £10 |
51–100 | £18 |
101 or more | £26 |
Working 80 hours at home each month gives an annual flat-rate deduction of £216. The business share of telephone and internet bills can be claimed separately because these are outside the flat rate.
The eligibility threshold is 25 hours per month, not per week. Working fewer hours does not automatically prevent a claim using actual costs. HMRC’s simplified home-working rates
Potential costs include heating, electricity, Council Tax, rent or mortgage interest. Mortgage capital repayments are excluded. Use a reasonable allocation reflecting the relevant space, time and nature of each cost. HMRC’s home-working guidance
For an illustrative electricity calculation, assume:
The resulting business share is £1,200 ÷ 5 × 50% = £120.
That calculation works only if the assumptions reasonably reflect actual use. It is not a standard percentage to apply to every bill. A room containing energy-intensive equipment may need a different calculation.
Compare the methods using your own circumstances. Never deduct the same household cost twice.
Cash basis generally records income when received and expenses when paid. Traditional accounting, also called accruals accounting, generally recognises income earned and costs incurred for the relevant period, even where payment occurs later. HMRC’s accounting-method guidance
That distinction affects timing. An ordinary supplier bill received before the year end but paid afterwards will generally enter a later period under cash basis. Under traditional accounting, the period to which the cost relates matters.
For longer-lasting equipment, the route to relief also differs:
Purchase | Cash basis | Traditional accounting |
Qualifying laptop, tools or machinery | Generally an expense when paid | Generally considered under capital allowances |
Business car | Separate capital-allowance rules unless mileage is used | Separate capital-allowance rules unless mileage is used |
Routine equipment repair | Generally an expense when paid | Generally an expense for the relevant period |
Private-use adjustments still apply. Accounting depreciation is not itself a tax deduction. HMRC’s equipment guidance
Capital allowances do not always mean spreading relief over several years. The Annual Investment Allowance can provide a full deduction for qualifying plant and machinery within its limits. Cars are excluded from that allowance. HMRC’s Annual Investment Allowance guidance
Treat a repair, replacement asset and property improvement as separate questions. A large invoice should be reviewed before being placed automatically in “repairs”.
A training course does not have to repeat an existing qualification to qualify. Relevant learning can develop skills that support your current business, including bookkeeping, administrative skills and adapting to industry technology.
A designer learning software for existing services may qualify. Retraining to establish an unrelated business normally does not. Keep the course outline and a brief explanation of how it supports the trade. HMRC’s training guidance
Business bookkeeping and accounts-preparation fees generally qualify. HMRC also accepts normal recurring work relating to the tax liability on trading profits. However, personal tax-return work, investment matters and capital-gains calculations should not automatically be included. Ask for a breakdown where professional fees cover both business and personal matters. HMRC’s accountancy-fee guidance
Small recurring costs are easily missed. Review software renewals, hosting, professional subscriptions, card-processing fees and purchases paid from personal accounts.
For an online seller, distinguish sales income from the amount a platform transfers after deducting fees. Reconcile the sales and charges so that fees are neither omitted nor deducted twice.
Commercial sponsorship may qualify where it meets the business-purpose test. It is not interchangeable with a personal charitable donation. HMRC’s marketing and subscriptions guidance
Under traditional accounting, a qualifying trading debt already included in turnover may be deductible when it is irrecoverable. An overdue invoice alone is not enough: keep evidence supporting the write-off.
For example, a £900 fee included in income that becomes wholly irrecoverable may produce a £900 deduction, assuming it qualifies and VAT is not involved. Under cash basis, the unpaid fee would normally never have entered taxable receipts, so there is no separate bad-debt deduction. HMRC’s bad-debt guidance
New businesses should also review spending before their start date. Certain qualifying revenue expenses incurred within seven years before trading begins can receive relief if they would have been deductible had the business already been trading and are not otherwise deductible.
This is not blanket relief for every start-up purchase. Equipment, advance stock purchases and expenditure already relieved elsewhere need their own treatment. Keep dates, invoices and the connection to the trade. HMRC’s pre-trading expenditure rules
A business-expense deduction and a VAT reclaim are different calculations.
Under cash basis, VAT-registered businesses can record income and expenses including or excluding VAT, but must use a consistent approach. If using VAT-inclusive figures, payments of VAT to HMRC are recorded as expenses and VAT repayments as income. The applicable VAT scheme and any restrictions also need consideration. HMRC’s VAT recording guidance
For example, under a VAT-exclusive approach, a wholly allowable £120 purchase comprising £100 plus £20 fully recoverable VAT produces a £100 expense deduction. Do not reclaim that £20 and also leave it in the expense figure under that approach.
If VAT cannot be recovered, it may form part of the deductible cost or asset cost, depending on the purchase. Naail & Co’s bookkeeping and VAT services can help you apply the correct treatment consistently.
Personal pension contributions may receive tax relief, but they are not a sole trader’s ordinary operating expense. Gift Aid also follows separate personal tax-relief rules rather than reducing trading profit as a business donation. HMRC’s pension relief guidance, HMRC’s Gift Aid guidance
Common costs to leave out of trading deductions include:
These exclusions are addressed in HMRC’s guidance on drawings, clothing, entertainment, domestic help and financial costs.
Where eligible, you can use the trading allowance instead of actual expenses. You cannot deduct both against the same trading income or combine the allowance with capital allowances for that income.
Example with £3,500 trading income | Deduction | Taxable trading income |
Claim £300 actual allowable costs | £300 | £3,200 |
Claim the trading allowance instead | £1,000 | £2,500 |
Claim actual costs where they total £1,600 | £1,600 | £1,900 |
The allowance can suit a low-cost side business, but eligibility comes first. It does not apply to partnership trading income and is restricted for certain connected-party income. It is also a single annual allowance across relevant trading income, not £1,000 for every separate side business. HMRC’s trading allowance guidance
These illustrations show the questions to ask, rather than automatic entitlements for everyone in the same occupation.
Business | Potential expenses | Point requiring care |
Self-employed electrician | Materials, safety equipment, tool repairs and qualifying travel | Distinguish vehicle mileage from actual costs and assess journeys individually. |
Freelance consultant | Software, professional insurance, coworking and business calls | Separate private phone use and client entertaining. |
Online retailer | Stock, packaging, advertising, platform fees and delivery | Reconcile gross sales to net payouts and apply the correct stock treatment. |
Consider a consultant using cash basis, with no VAT registration, whose illustrative figures are:
Item | Amount |
Business receipts | £42,000 |
Recorded expenditure | £8,000 |
Less private purchases included in that expenditure | (£500) |
Less private share of mixed-use bills | (£300) |
Less client entertainment | (£200) |
Allowable expenses | £7,000 |
Taxable trading profit before any other adjustments | £35,000 |
This assumes all remaining expenditure qualifies, has been paid and requires no further capital or timing adjustment. The £35,000 is trading profit, not the final tax bill: personal allowances, other income and separate reliefs still matter.
Claim allowable expenses through the self-employment reporting relevant to your Self Assessment return. Your accountant or tax software can help identify the appropriate categories and any separate capital-allowance entries.
Before filing:
You do not normally attach receipts to the return, but HMRC can ask to see evidence. HMRC’s claiming guidance
If your records need reviewing before submission, our Self Assessment service can help you establish the correct figures.
First ask the supplier for a duplicate invoice or receipt. If that is unavailable, reconstruct the purchase using statements, order confirmations and other evidence. A bank entry alone may not explain what was bought or its business purpose.
Where records cannot be replaced, HMRC says to do your best to provide figures and identify estimated or provisional amounts on the return. Provisional figures must be replaced with actual figures when available.
Keep self-employed records for at least five years after the 31 January submission deadline. For a 2025/26 return filed on time, that normally means until at least 31 January 2032. Longer retention can be necessary for late returns or an ongoing check. HMRC’s record-retention and missing-records guidance
You can normally amend a Self Assessment return within 12 months of its filing deadline. The usual amendment deadline for 2024/25 is 31 January 2027; for 2025/26 it is 31 January 2028.
If that window has closed, overpayment relief may be available within four years after the relevant tax year ends, subject to its conditions. This is a separate claim, not an unrestricted extension of the amendment deadline.
Do not simply add a forgotten earlier-year expense to the current return. Establish the correct period and correction route. If you discover an excessive claim, correct it promptly; additional tax, interest and potentially penalties may follow. HMRC’s return-correction guidance
The strongest expense records answer three questions: What did you buy? Why did the business need it? How did you calculate the deductible amount?
A short note made at the time can resolve uncertainty months later. Record the purpose of an unusual journey, the link between a course and your work, or the basis for a shared bill’s business percentage.
Review recurring subscriptions and personal-account purchases regularly. Then give larger or unusual transactions separate attention. An automated category is a bookkeeping suggestion, not a tax decision.
Finally, do not spend simply to obtain relief. A £1,000 purchase that saves £200 of Income Tax still costs £800 after that saving, before considering other effects. Buy what the business needs and claim the relief properly.
A complete expenses claim captures legitimate costs, excludes private spending and applies the right treatment to shared bills, equipment and unusual transactions. Good records make that process easier and help you explain the figures if HMRC asks.
Naail & Co Chartered Certified Accountants and Tax Advisors provides accounting support for self-employed businesses, helping you review deductions and prepare your tax return with a clearer understanding of your position.
Whether you are filing your first return, reviewing years of inconsistent records or checking a significant purchase, bring us the details and we can help you work through the next steps.
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The Self Employed allowable expenses list UK covers qualifying business costs such as office supplies, stock, business travel, insurance, advertising, staff wages and relevant training. HMRC generally requires expenditure to be incurred wholly and exclusively for the trade. Mixed-use costs must be restricted to their identifiable business portion, while equipment may require capital allowances rather than an ordinary expense deduction. HMRC guidance
Claiming allowable self employed expenses reduces your taxable trading profit, which can reduce Income Tax and Class 4 National Insurance. For example, £40,000 of business income minus £8,000 of allowable expenses leaves £32,000 of trading profit before other adjustments. A deduction is not a pound-for-pound tax refund: the actual saving depends on your tax rates, allowances and wider circumstances. HMRC guidance
The £1,000 trading allowance may be beneficial when you qualify and your total allowable deductions are below £1,000. You cannot combine it with actual expenses or capital allowances against the same trading income. Compare both calculations before filing, and remember that eligibility restrictions apply. The allowance is shared across relevant trading income; it is not a separate £1,000 deduction for every side business. HMRC guidance
For 2026/27, eligible self-employed car and goods-vehicle mileage is deductible at 55p per business mile for the first 10,000 miles and 25p thereafter. For 2025/26, the first rate was 45p; motorcycles remain at 24p. Keep a business mileage log and check eligibility. The mileage method replaces covered vehicle purchase and running costs, so do not also deduct fuel, servicing or insurance. HMRC mileage rates
Yes, you can claim an appropriate business share of qualifying household costs or use HMRC’s simplified home-working rates where eligible. The monthly flat rates are £10 for 25–50 business hours, £18 for 51–100 hours and £26 for 101 hours or more. Business telephone and internet costs can be calculated separately. Under the actual-cost method, keep a reasonable allocation based on business use. HMRC guidance
Yes, qualifying business equipment can receive tax relief, but the method depends on your accounting basis and the asset. Under cash basis, computers and tools are generally deducted when paid for. Under traditional accounting, longer-lasting equipment generally falls within capital allowances. Restrict claims for private use, and check cars separately. Capital allowances can sometimes provide full upfront relief rather than deductions spread over several years. HMRC equipment guidance
You need reliable evidence supporting your expense claims, although receipts are not normally submitted with your tax return. Keep invoices, receipts, mileage logs and relevant calculations. If a receipt is missing, request a duplicate and reconstruct the transaction where possible. Records normally need retaining for five years after the relevant 31 January filing deadline; disclose estimated or provisional figures where HMRC requires this. HMRC record-keeping guidance
An expense can be disallowed because tax treatment depends on its purpose and the applicable rules, not the account used to pay it. Private purchases, ordinary clothing and client entertainment generally remain non-deductible. Conversely, a genuine business expense paid personally may qualify. Review automated bookkeeping categories carefully: a bank transaction proves payment but does not establish entitlement to tax relief. HMRC’s business-purpose test
Yes, you can normally amend a Self Assessment return within 12 months of its filing deadline. For 2025/26, the usual amendment deadline is 31 January 2028. After that, overpayment relief may be available within four years of the tax year’s end, subject to conditions. Do not simply add an earlier-year expense to your current return; establish the correct period and correction route. HMRC correction guidance
Ask an accountant before filing if you have substantial mixed-use costs, equipment purchases, bad debts, pre-trading expenditure or uncertain deductions. A review can identify missed relief and unsupported claims. Fees depend on the records and work involved, so request a clear scope and quote. Business accounts and bookkeeping fees generally qualify for relief, but personal tax work needs separate consideration. HMRC professional-fee guidance
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