Key facts (2026): Self-employed workers can deduct allowable business expenses from their taxable income, reducing the tax they pay. Qualifying expenses must be wholly and exclusively for business purposes. Common claims include office costs, travel, equipment, professional fees, advertising, and a proportion of home running costs.

Getting your expenses right is one of the most valuable things a self-employed person can do — every £100 of legitimate expenses saves £20–£45 in tax depending on your rate. Yet many self-employed people either miss legitimate claims or risk HMRC scrutiny by claiming personal costs as business expenses. This guide sets out what qualifies clearly.

Allowable Business Expenses — Full Categories

Office costs: stationery, printer ink, postage, computer equipment (may need to be capital allowances for larger items). Travel: fuel, mileage at HMRC approved rates (45p/mile for first 10,000 miles, 25p/mile after), parking, train fares, flights for business. Accommodation for overnight business travel. Clothing: only uniforms and protective gear — not everyday business attire. Staff costs: wages, subcontractor fees, pension contributions. Professional fees: accountant, solicitor fees for business purposes. Advertising and marketing: website costs, social media ads, business cards. Bank charges on business accounts. Insurance: business insurance, professional indemnity. Training: courses and books to maintain or improve business-related skills (not to acquire new skills for a different trade).

Home Office Expenses — Two Methods

Method 1 — HMRC flat rate: £10/month (25–50 hours/month), £18/month (51–100 hours/month), £26/month (101+ hours/month). Simple but limited. Method 2 — Actual costs: calculate the proportion of your home used exclusively for work (by rooms or floor area) and apply that proportion to your total home running costs (rent, mortgage interest element, utilities, council tax). This typically produces a larger claim but requires detailed records and care about the 'exclusive use' requirement.

What You Cannot Claim

Personal costs: clothing, personal phone calls, food (except subsistence during business travel), personal gym membership, commuting to a regular workplace. Capital costs: large equipment purchases go through capital allowances rather than direct expense deduction (though the Annual Investment Allowance is generous at £1,000,000). Fines and penalties: HMRC penalties, parking fines.

Our Verdict

Keep meticulous records of all business expenses — receipts, invoices, and bank statements — from day one of self-employment. Digital accounting tools like FreeAgent, QuickBooks, or Xero make this straightforward. The mileage rate claim (45p/mile) is often overlooked but highly valuable for those using their personal car for business. An accountant's first review often pays for itself by identifying missed claims.

Frequently Asked Questions

What expenses can self-employed claim UK?

Office costs, travel (including mileage at 45p/mile), equipment, professional fees, advertising, staff costs, home office proportion, and business insurance — all wholly for business purposes.

Can I claim home office costs self-employed?

Yes — either using HMRC's flat rate (up to £26/month) or a proportion of actual home costs based on space and hours used.

What is the mileage rate for self-employed UK 2026?

45p per mile for the first 10,000 business miles per year, then 25p per mile. This covers fuel, wear and tear, and insurance for business use.

Disclaimer: For informational purposes only. Verify with gov.uk or qualified professionals before making decisions.

Last updated: April 2026 · Author: Chandraketu Tripathi