Self-employed allowable expenses: 2026/27

Self-Employed Allowable Expenses (2026/27): Complete HMRC Checklist

Complete guide to what UK self-employed sole traders can deduct from trading profit in 2026/27. Section 34 ITTOIA 2005 "wholly and exclusively" test (Mallalieu v Drummond [1983] precedent). 8 expense groups × 30+ categories with allowable / not allowable / conditional status. Simplified vs actual cost comparison for vehicle + home-as-office. £1,000 Trading Allowance alternative. Capital vs revenue distinction (British Insulated [1926]). Pre-trading expenses (7-year rule). Training: Donna Smith FTT precedent on update-vs-new-skill. 12-item FAQ covering common borderline cases.

2026/27 expenses framework

The killer test

Wholly + Exclusively

Section 34 ITTOIA 2005. ANY personal benefit = entire expense disallowed.

Trading Allowance

£1,000

Annual alternative to actual expenses

Mileage AMAP

45p / 25p

First 10k miles then reduced rate

8-group expense checklist (30+ items)

Status legend: ✅ Allowable | ❌ Not allowable | ⚠️ Conditional / capital allowance route

Premises

Expense Status Notes
Rent of business premises Full deduction. Includes rates, utilities for business space.
Use of home as office Simplified £10-£26/month OR actual apportioned by hours + rooms.
Business rates For commercial premises only.
Repairs and maintenance Revenue repairs only - improvements are capital (separate AIA).

Travel & vehicle

Expense Status Notes
Business mileage (own car) 45p/mile first 10,000 business miles, 25p/mile after, OR actual proportional costs.
Public transport for business Train, bus, tube fares for genuine business trips. Not commute.
Hotel + meals while away overnight Reasonable cost only. Lavish hotels challenged by HMRC.
Vehicle purchase CAPITAL not revenue - claim via AIA / capital allowances instead.
Parking fines / speeding Section 54 ITTOIA 2005 specifically blocks. Parking charges (legal) allowable.

Equipment & tools

Expense Status Notes
Computer, phone, equipment under £200 Revenue if cheap/small. Larger items via capital allowances.
Software subscriptions Accounting software, professional tools, cloud services.
Tools, machinery, plant ⚠️ Claim via £1m AIA or 18% main pool capital allowance.
Protective / safety equipment Hi-vis, hard hats, safety boots, PPE.

Staff & subcontractors

Expense Status Notes
Employee wages + NICs Plus pension contributions, training, uniforms provided.
Subcontractor payments If subcontractor is genuinely separate business (not IR35-caught).
Wages to family members ⚠️ Only if work is genuinely performed at market rate. Sham arrangements rejected by HMRC.

Professional

Expense Status Notes
Accountancy fees Including SA preparation, year-end accounts, advice on business matters.
Legal fees (revenue) Debt collection, employment law, contract disputes (revenue).
Legal fees (capital) Buying property, share issues, M&A - capital, not revenue.
Professional indemnity insurance Solicitors, accountants, consultants, IT contractors.
Trade union / professional body subs CIMA, ICAEW, RICS, etc. if relevant to business.

Marketing

Expense Status Notes
Advertising & marketing Google Ads, Facebook Ads, print, sponsorship, SEO.
Website hosting + domains Annual fees for business website infrastructure.
Business cards + stationery Genuine business use only.

Finance

Expense Status Notes
Bank charges + interest Business account fees + loan interest. Personal loan interest NOT allowable.
Credit card interest (business) Only on business credit cards / for business purchases.
Bad debts written off Specific provision for actual unrecoverable debts. General provisions disallowed.

Other

Expense Status Notes
Training (existing skills update) Refreshing existing professional skills. Donna Smith v HMRC (FTT 2018) precedent.
Training (NEW skill / career change) New trade qualifications NOT allowable - personal capital not business expense.
Pension contributions (yours) Personal pension contributions reduce ANI but NOT trading profit. Different relief.
Clothes (general) Even "work suit" clothes are personal. Mallalieu v Drummond [1983] HL.
Entertainment of clients Section 45 ITTOIA 2005 blocks. Staff entertainment up to £150/head allowable.
Gifts to clients (under £50) Branded promotional items under £50 per recipient per year.

Simplified vs actual costs

Section 94H ITTOIA 2005 provides flat-rate alternatives to apportioned actual costs in three categories. Choose method per category per tax year.

Category Simplified rate When actual usually wins
Vehicle mileage 45p first 10k miles / 25p after 50k+ miles/year high-cost vehicles
Use of home (25-50 hrs/mo) £10/month Rarely - too low to need actual route
Use of home (51-100 hrs/mo) £18/month Dedicated home office 20%+ of property
Use of home (101+ hrs/mo) £26/month Full-time home worker with dedicated office
Live-in business premises £350-£650/month by occupants B&Bs, guesthouses, residential care

Key UK case law

  • Mallalieu v Drummond [1983] 2 AC 861 (HL): female barrister's court clothing disallowed. "Dual purpose" of warmth + decency failed the exclusive test. Cornerstone of clothing-expense disallowance.
  • British Insulated and Helsby Cables v Atherton [1926] AC 205 (HL): "enduring benefit" test for capital vs revenue. If expenditure brings into existence an asset or advantage that endures, it's capital.
  • Banerjee v HMRC [2010] EWCA Civ 87: medical doctor's part-time training in new specialty disallowed. Cornerstone of "new skill vs existing-skill update" rule.
  • Donna Smith v HMRC (FTT 2018, TC06554): tax adviser's update training allowed even where it covered some new technical areas. Nuanced the Banerjee strict line.
  • Caillebotte v Quinn [1975]: self-employed sub-contractor's lunch expenses while working away disallowed - meals are personal even when working at site away from home.
  • Bentleys, Stokes and Lowless v Beeson [1952]: client entertainment disallowance pre-codified in Section 45 ITTOIA 2005.

Frequently asked questions

What is the "wholly and exclusively" test?

Section 34(1)(a) Income Tax (Trading and Other Income) Act 2005: an expense is deductible from trading profit only if "wholly and exclusively for the purposes of the trade". The leading case is Mallalieu v Drummond [1983] 2 AC 861 (HL) where the House of Lords disallowed a female barrister's deduction for sober black court clothes - even though the clothing was specifically for court, the House held there was also a "dual purpose" of warmth and decency, so the test failed. The "exclusively" word is the killer - if there's ANY personal benefit, the entire expense is disallowed (no apportionment for split-purpose items). The "wholly" word covers amount - only the trade-related portion is allowable. Apportionment IS permitted under Section 34(2) where an expense can be split mathematically (e.g. home utilities by floor area + hours used for business).

What is the £1,000 Trading Allowance?

Section 783A ITTOIA 2005 - a £1,000 flat-rate deduction available as an ALTERNATIVE to claiming actual expenses. Below £1k gross income: no need to register for Self Assessment, income automatically tax-free. Above £1k: register for SA, then choose £1,000 Trading Allowance OR actual expenses (whichever is higher). Worked example: side-hustle income £3,500, actual expenses £400. Option A: Trading Allowance £1,000 deduction = £2,500 taxable. Option B: actual expenses £400 deduction = £3,100 taxable. Trading Allowance wins by £600. Switch between methods each tax year to optimise. The Trading Allowance does NOT apply to partnership income, income from a company you control, or income from your employer. See our side hustle tax calculator.

Simplified vs actual expenses - which is better?

Simplified expenses (Section 94H ITTOIA 2005) are HMRC-set flat rates for three common expense areas: vehicle costs, use-of-home, and live-in business premises. Vehicle simplified: 45p/mile first 10,000 business miles, 25p/mile after (matches employee AMAP). Use-of-home simplified: £10/month for 25-50 business hours, £18/month for 51-100 hours, £26/month for 101+ hours. Live-in business premises: £350/month single occupant, £500 two, £650 three. Actual expenses: claim mathematically apportioned real costs (fuel + insurance + depreciation by business-mile %, utilities by floor area × hours-used). Simplified usually wins for: small / occasional business use, simple home offices, low-mileage drivers. Actual usually wins for: high-mileage commercial vehicles (45p/mile rarely covers actual cost over 10k miles), dedicated home offices (>20% of home for full business use). Once you choose for a tax year, you must apply consistently across that category. Switch year-to-year as circumstances change.

Use of home as office - how much can I claim?

Two approaches. Simplified flat rate: £10/month for 25-50 hours of business use per month, £18/month for 51-100 hours, £26/month for 101+ hours. Maximum £312/year. Apportioned actual: take total household running costs (gas, electricity, water, council tax, broadband, building insurance, mortgage interest if applicable) and apportion by (a) floor area used for business / total floor area, AND (b) hours used for business / total hours per week. Worked example: 10% of floor area + 40 hours/week business use. Annual household costs £4,800. Apportionment: £4,800 × 10% × (40/168 hours per week) = £114. Repeat monthly. Cleaning, repairs, rent (if renting): same apportionment. Mortgage CAPITAL repayments: NOT allowable (capital). Mortgage INTEREST: allowable on apportioned basis. Council Tax: allowable on apportioned basis (some advisors argue not - check current HMRC guidance BIM47820). Most self-employed find simplified easier; actual wins for full-time home-based workers with dedicated office space.

Can I claim training course costs?

Depends on whether it's UPDATING existing skills (allowable) or LEARNING NEW skills (not allowable). Allowable: refreshing existing professional skills (CPD courses for accountants / solicitors / doctors), product training for software you use, conference attendance in your existing field. NOT allowable: training to qualify in a new trade, courses leading to new professional qualifications, MBA programmes (almost always disallowed as new-skill acquisition). The leading case is Banerjee v HMRC [2010] EWCA Civ 87 where the Court of Appeal denied a deduction for a medical doctor's part-time training in a new specialty. Donna Smith v HMRC (FTT 2018, TC06554) nuanced this - the FTT allowed deduction for a tax adviser's update training even though it covered some new technical areas, on the basis that the training maintained currency in the existing trade. The line is fuzzy. Conservative approach: claim if the training is clearly a refresh / update; consult an accountant if it's borderline new-skill.

What's the mileage rate?

AMAP (Approved Mileage Allowance Payments) rates - same for self-employed and employees. 45p/mile for the first 10,000 business miles in a tax year, 25p/mile thereafter. Frozen since 2002. Real-terms erosion ~50% over 23 years. ALTERNATIVE: claim actual costs proportional to business mileage (fuel + insurance + depreciation + repairs apportioned by business-mile %). Worked decision: 5,000 business miles per year, 15p actual cost per mile. Simplified: 5,000 × 45p = £2,250. Actual: 5,000 × 15p = £750. Simplified wins by £1,500. For high-mileage drivers (50k+/year) actual usually wins because the 25p rate after 10k is well below typical fuel-only cost. Bicycle business mileage: 20p/mile, same allowance flat rate. Motorcycle: 24p/mile. Business mileage means trips for business purposes - commute home-to-regular-workplace is NOT business mileage (commute is non-allowable).

Capital vs revenue - what is the distinction?

Section 33 ITTOIA 2005 specifically disallows capital expenditure from trading profit deductions. Capital: long-lasting items that benefit the business for multiple years - vehicles, machinery, premises, plant, fixtures. Claimed via Capital Allowances regime instead (Annual Investment Allowance £1m + 18%/6% main pool / special rate pool). Revenue: short-lived items consumed in the business year - stock purchased + sold, fuel, utilities, wages, marketing, repairs (not improvements). The "enduring benefit" test from British Insulated and Helsby Cables v Atherton [1926] AC 205 (HL): if the expenditure brings into existence an asset or advantage that endures, it's capital. Common borderline items: server replacement (often allowed as repair if functionally identical); shop refit (improvement = capital; like-for-like replacement = revenue); website (annual hosting = revenue; one-off design / build = often capital). HMRC's BIM35000+ manual provides extensive examples. The capital allowances regime gives 100% first-year deduction on most plant + machinery via the £1m AIA, so the distinction matters less than it used to for cash-flow purposes.

Can I claim my phone, laptop, internet costs?

Yes, apportioned for business use. Phone: separate business mobile = 100% allowable; mixed-use personal phone = apportion by business-call %. Itemised bill helps. Laptop / computer: bought specifically for business and used primarily for business = 100% allowable as small revenue item OR via AIA capital allowance if expensive. Mixed-use personal laptop = apportion by hours / use. Broadband / Wi-Fi: home internet apportioned similarly to home utilities (business-hours / total-hours × business floor area / total). Standard 25-35% claim is commonly accepted by HMRC for genuine home workers. Standalone equipment under £200: typically just claimed as revenue expense, no need for capital allowances. Common error: claiming 100% of household phone bills when there's significant personal use - HMRC will challenge on enquiry. Keep records of business calls if claiming high percentage.

Pre-trading expenses - can I claim costs before I started?

Yes, up to 7 years before the trade commences (Section 57 ITTOIA 2005). Pre-trading expenses are deducted in the FIRST year of trading as if incurred on day one. Must satisfy the wholly-and-exclusively test - so genuine business-setup costs only, not personal preparation. Allowable pre-trading: market research costs, professional fees on business formation, training in existing skills relevant to the trade, business-plan consulting, initial inventory purchase, equipment bought for the business (capital → claim via AIA in year 1). NOT allowable: training to acquire the trade skills (new qualification), personal living costs during setup period, capital costs of business property (claim via separate capital allowances mechanism). Keep itemised receipts + dates - HMRC may ask for the trade-commencement date justification. Common error: claiming "starting a business" courses as allowable - typically NEW skill, disallowed under Banerjee precedent.

Can I claim my own pension contribution as a business expense?

NO - this is one of the most common self-employed errors. Personal pension contributions reduce your Adjusted Net Income (for £100k taper / HICBC / TFC cliff purposes) but do NOT reduce trading profit on the SA. Personal pension contributions get tax relief through a separate mechanism: the pension provider adds 20% basic-rate relief at source ("relief at source") and higher-rate / additional-rate relief is claimed through Self Assessment. So a £1,000 contribution from your bank becomes £1,250 in the pension; higher-rate taxpayer gets a further £250 relief via SA. Different from corporate "EMPLOYER" pension contributions which ARE deductible from company profit. Confusingly the self-employed treatment differs from sole-trader vs limited-company. Limited company directors who pay themselves a salary + dividend should make EMPLOYER pension contributions from the company - those reduce CT bill. Self-employed sole traders make PERSONAL contributions - those reduce SA tax via the dual-relief mechanism. See our maximum pension contribution calculator.

Can I claim entertainment + meals for clients?

NO for client entertainment. Section 45 + 46 ITTOIA 2005 specifically disallows business entertainment of customers / clients. This applies whether you're sole trader or limited company. Includes meals, drinks, sports tickets, theatre tickets, holiday entertainment - ALL disallowed regardless of business purpose. STAFF entertainment IS allowable up to £150 per head per year for an "annual function" open to all staff (Section 264 ITEPA 2003 + Section 50 ITTOIA 2005). Christmas party, summer BBQ, end-of-year event. Must be available to all employees (or all in a location/department) - not just directors. Above £150/head: entire amount becomes taxable benefit for the employee. Gifts to clients: allowable up to £50 per recipient per year IF carrying conspicuous advertisement of the business AND not food/drink/tobacco/vouchers. Branded merchandise, calendars, diaries, mugs typically qualify. Food/drink hampers do NOT (gift restriction). The £50 limit is the deal-breaker - one £75 gift to a client is fully disallowed, not "the first £50 allowable + £25 disallowed".

What records do I need to keep?

Section 12B Taxes Management Act 1970 + Self Assessment requirements. Keep ALL receipts, invoices, bank statements, mileage logs, customer/supplier records for at least 6 years after the SA filing deadline. Common format: physical receipt + scanned digital copy. Most self-employed use accounting software (FreeAgent £19/mo, Xero £15/mo, QuickBooks £12/mo, Bokio free, Pandle free) which captures records as you go. HMRC's spot-check rate on SA returns is ~1 in 60 normally, higher for: high-expense ratios (>50% of turnover), cash-business sectors (taxis, builders, hairdressers), late filers, and specific HMRC compliance campaigns. Records expected: dated receipts, supplier name + VAT reg if applicable, payment method (cash vs card), business purpose. Mileage log entries: date, miles, business purpose, start/end locations. From April 2026 MTD ITSA mandation for self-employed earning over £50k requires DIGITAL records + quarterly reporting via approved software. From April 2027 for £30k+. See our MTD ITSA guide.

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