What a deduction is actually worth to you
This guide is about what you can claim as a sole trader, and what each claim is really worth. Every £1 of allowable expense you claim cuts your taxable profit by £1. What that saves you is your marginal rateThe rate of tax on your next pound of income - your Income Tax band plus, for the self-employed, Class 4 National Insurance. It is what a £1 deduction actually saves you. - your Income Tax rate plus the Class 4 National InsuranceClass 4 National Insurance: National Insurance paid by the self-employed on their profits, on top of Income Tax. For 2026/27 it is 6% on profits between £12,570 and £50,270, and 2% above that. you pay on profit. So an expense is best thought of not as money you recover, but as a cost the taxman shares with you. How big his share is depends on where your profit sits, and on whether you pay Scottish or rest-of-UK Income Tax. For 2026/27:
- Most sole traders pay basic-rate Income Tax (20%) and Class 4 NI (6%), so £100 of expenses saves £26.
- In the rest-of-UK higher-rate band (profit over £50,270) it is 40% + 2% = £42 per £100.
- A Scottish trader earning between £43,663 and £50,270 saves £48 per £100. The Scottish higher rate of 42% starts well below the £50,270 point where Class 4 NI drops to 2%, so at ordinary rates this is the highest-relief band for the self-employed anywhere in the UK (only the £100,000 taper below beats it).
- In the £100,000 to £125,140 band, where the Personal AllowanceThe amount of income you can earn each year before income tax. It is £12,570 for 2026/27, tapering away by £1 for every £2 of income over £100,000. is withdrawn, £100 of expenses saves about £62 in the rest of the UK and about £70 in Scotland - because cutting your profit there also hands back some tax-free allowance.
Simplified or actual? Check your own numbers
For your home, vehicle and phone, enter what you spend. The comparator shows the simplified flat rate against the actual apportioned cost for each, picks the bigger deduction, and - if you add your profit - reads the same tax engine as our calculators to show the saving in pounds. You can mix methods across categories.
Careful: the £6 a week is not for you
The most common mix-up in this area is the £6 a week working-from-home figure. That is the employee scheme, and it is worth flagging twice over. First, it was never yours: as a sole trader you use the simplified home-working bands (£10, £18 or £26 a month) or the actual-cost method instead. Second, employees cannot claim it either for 2026/27 - HMRC withdrew working-from-home relief for the year, though the previous four years can still be claimed. So a guide telling a self-employed reader to claim £6 a week is doubly wrong. Your home-working claim is covered in the comparator above and the detail below.
Cash basis or traditional accounting? The default changed in 2024/25
Before you decide what to claim, you need to know when you can claim it - and that depends on your accounting method. Since 6 April 2024, cash basisThe default way sole traders record income and expenses since 6 April 2024: you count money when it is actually received or paid, not when invoiced. Traditional accruals accounting is the alternative. has been the default for sole traders. Under cash basis you record income and expenses only when money actually changes hands - you claim an expense in the year you pay it, not the year you are billed. Before 2024/25 cash basis was an opt-in scheme you could only use if turnover was £150,000 or less; now any sole trader can use it.
The method changes what counts as an expense:
- Under cash basis, most equipment you buy and keep (computers, tools, machinery) is a normal allowable expense - you do not route it through capital allowancesTax relief for assets you buy and keep for the business, such as cars or equipment. The Annual Investment Allowance lets most businesses deduct the full cost in the year of purchase.. Cars are the exception (see below).
- Interest and bank charges on business borrowing are allowable.
- You would choose traditional (accruals) accounting instead - recording income and costs by invoice date - if your business carries significant stock, or if you need formal accounts to raise finance. You tell HMRC which you used on your Self AssessmentHMRC's system for reporting income and gains not taxed at source. The online return and payment deadline is 31 January after the tax year ends. return.
The rule everything hangs on: wholly and exclusively
Whatever your method, every expense must pass one test: it must be incurred wholly and exclusivelyThe core test for a business expense: it must be incurred only for the purposes of your trade. A cost that also serves a private purpose and cannot be split is disallowed (HMRC manual BIM37000). for your trade (HMRC manual BIM37000). If a cost serves both your business and your private life and the two cannot be separated, it is disallowed outright - the "dual purpose" trap. The classic example is an everyday suit worn to client meetings: because it also provides ordinary warmth and decency, none of it is claimable.
The practical escape is apportionment. Where a cost has an identifiable business share, you claim that share. A mobile phone or broadband bill is the everyday case: work out the business proportion of your use and claim that - HMRC expects you to keep the basis you used. (Phone and internet are specifically not covered by the working-from-home flat rate below, so you claim their business share separately - that is why the comparator has its own box for them.)
Working from home and your vehicle: flat rate or actual cost?
For home and vehicle running costs you can use HMRC's simplified expenses flat rates instead of working out actual costs. They save record-keeping, but they often under-claim - so treat them as a floor, not the answer. The comparator above puts both side by side on your figures; the detail is here.
Working from home is a flat monthly rate based on hours worked there: £10 a month for 25 to 50 hours, £18 for 51 to 100, and £26 for 101 or more - at most £312 a year, and only if you work at least 25 hours a month at home. If you have a dedicated room and high energy bills, the actual-cost method (a fair proportion of heat, light, council tax and so on) can be worth far more.
Vehicle mileage is 55p a mile for the first 10,000 business miles and 25p after that (24p for motorcycles) for 2026/27 - the first-10,000 rate rose from 45p on 6 April 2026, the first rise in years, so most sites still quote it wrong. There is a catch worth deciding before you start: once you use the flat mileage rate for a vehicle, you must keep using it for that vehicle, and you cannot also claim capital allowancesTax relief for assets you buy and keep for the business, such as cars or equipment. The Annual Investment Allowance lets most businesses deduct the full cost in the year of purchase. on it. For a cheap-to-run, high-mileage car the flat rate usually wins; for an expensive vehicle, actual costs plus capital allowances may beat it.
Buying equipment: expense or capital allowance?
If your actual-cost choices lead you to buy a vehicle or equipment, the next question is whether the purchase is an ordinary expense or a capital allowanceTax relief for assets you buy and keep for the business, such as cars or equipment. The Annual Investment Allowance lets most businesses deduct the full cost in the year of purchase.. The answer turns on your accounting method:
- Cash basis (the default). Most things you buy and keep - a laptop, tools, machinery, a van - are ordinary allowable expenses, deducted in full in the year you pay. The single exception is a car, which always goes through capital allowances.
- Traditional accounting. Equipment, machinery and business vehicles go through capital allowances. The Annual Investment Allowance lets you deduct the full cost of most plant and machinery in the year you buy it, up to £1 million a year - far above what a typical sole trader spends. Cars are excluded from it (they use writing-down allowances instead), and if you use an item privately as well you reduce the claim by the private-use share.
Either way, if you claim the £1,000 trading allowance (below) you cannot claim expenses or capital allowances on top.
The £1,000 trading allowance: claim it or your expenses, not both
Every sole trader gets a £1,000 trading allowanceA £1,000 tax-free allowance for casual or self-employed income. You can earn up to £1,000 before declaring, or deduct the flat £1,000 instead of your actual expenses - not both., and it is an either/or choice: you deduct the flat £1,000, or your actual expenses - never both. The decision is simple once you frame it as a breakeven. If your total allowable expenses for the year are under £1,000, claim the allowance: it is a bigger deduction and needs no records. If they are over £1,000, claim actual expenses. If your income for the year is under £1,000 you may not need to register or file at all. This matters most for side businesses - see the guide to being employed and self-employed at the same time.
"Can I claim it?" - the test, not the list
The question people really ask is not "what is on the list" but "can I claim this?" There is no list that settles it, because the answer comes from the wholly-and-exclusively test above. A useful shorthand: if you would have bought it anyway, whether or not you ran the business, it usually fails. Some recurring cases:
- Gym membership: no. It has an obvious private benefit, so it fails the dual-purpose test even if you feel it keeps you fit for work.
- Everyday clothing: no, even a suit bought only for work (settled in Mallalieu v Drummond). Only a genuine uniform, branded workwear, or protective gear qualifies.
- Client entertainment: no. Lunches, coffees and events to win or keep clients are never deductible.
- Coffee and meals while out working: generally no. Ordinary subsistence is a private cost; a reasonable meal on a genuine overnight business trip away from your normal base is an exception.
- Training: yes if it updates skills for your existing trade; no if it equips you for a new one.
- A mixed-use item (a phone, a laptop, a car): the business share only, apportioned.
And the misconception worth naming plainly: an expense is not a refund. Claiming £100 does not put £100 back in your pocket - it cuts your taxable profit by £100, and the tax on that profit falls by your marginal rate. That is the whole point of the first section.
Sole trader, company director or employee? Three different rulebooks
This guide is for sole traders. The word "expenses" means something different in each of the three ways you might earn, and content online routinely blurs them. If you are not a sole trader, the flat rates and rules above may not apply to you at all:
| You are a... | The test | Simplified flat rates? | Start here |
|---|---|---|---|
| Sole trader | Wholly and exclusively for the trade | Yes (this page) | This guide |
| Company director | Company costs, wholly and exclusively for the trade; different rules for a benefit in kind | No - companies cannot use them | Sole trader vs limited company |
| Employee | Wholly, exclusively and necessarily - a stricter test | No | Employed and self-employed |
The employee test carries an extra word, "necessarily", which is why an employee can claim far less than a sole trader for the same cost - and why the withdrawn £6 a week homeworking relief was an employee scheme, not one you can borrow.
Two claims people miss
- Pre-trading expenses. Costs you paid in the run-up to starting - up to 7 years before - that would have been allowable once you traded are treated as incurred on your first day of trading, and claimed then. Stock, equipment, a website and professional fees from before launch all commonly qualify.
- Digital record-keeping is here. Making Tax DigitalMaking Tax Digital: HMRC's move to digital record-keeping and quarterly updates. For Income Tax it applies to sole traders and landlords with income above set thresholds. for Income Tax began phasing in from April 2026; if it applies to you, you keep expense records digitally and report quarterly, which turns "what can I claim" from a once-a-year question into a four-times-a-year one. The thresholds and timing are in the Making Tax Digital for Income Tax guide.
Once you know what you can claim, the Self-Employed Tax Calculator shows how your expenses feed through to your Income Tax and Class 4 NI, and the Self Assessment guide covers how much to set aside. If you are weighing whether to incorporate, sole trader vs limited company sets out the tax mechanics on each side; and if your turnover is approaching the VAT registration threshold, the VAT registration trap explains why crossing it mid-year catches people out. This guide explains the mechanics of allowable expenses; it is not personal tax advice, and a complex case is worth an accountant's eye.
Frequently Asked Questions
Simplified or actual expenses - which leaves me better off?
How much does claiming an expense actually save me?
Is the £6 a week working-from-home allowance for me?
What is the mileage rate for 2026/27?
I bought a laptop or a van - is it an expense or a capital allowance?
Can I claim expenses from before I started my business?
What can I claim as a sole trader?
See what your expenses save on your own profit
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