Self-Employment Tax UK 2026/27 — Income Tax, National Insurance, Expenses and IR35

Can I Claim Startup Costs Before My Business Officially Launches? — UK 2026/27

Pre-trading expenses can be claimed as a deduction against your first year's trading profit. Find out which startup costs qualify and how to claim them on your Self Assessment return in 2026/27.

Tax information is based on HMRC rules for the 2026/27 tax year. Tax rules can change — always verify current rates at GOV.UK. This is not tax advice. Consider consulting a qualified tax adviser for your personal situation.

HMRC allows you to claim startup costs incurred up to seven years before your business officially starts — treating them as if they were spent on the first day of trading. Most new business owners do not know this rule exists, which means they miss out on valuable tax relief. Here is what qualifies and how to claim in 2026/27.

The Pre-Trading Expenses Rule

Under section 57 ITTOIA 2005 (for individuals) and section 61 CTA 2009 (for companies), costs incurred before trading begins are deductible if:

  1. They were incurred within the seven years before the trade starts
  2. They would have qualified as deductible revenue expenses had they been incurred after trading started
  3. They were incurred wholly and exclusively for the purposes of the trade

The costs are treated as if they were spent on the first day of trading — so they form part of the opening year’s expenses.

What Qualifies as a Pre-Trading Expense

Expense Qualifies? Notes
Market research and feasibility studies Yes Directly related to the new business
Professional advice (solicitor, accountant) Yes For business setup, not personal matters
Website design and domain registration Yes For the business website
Advertising and marketing before launch Yes Promoting the new business
Business insurance (before first client) Yes Taken out before trading begins
Equipment testing and trials Yes To assess business viability
Training to refresh existing skills Yes E.g. refresher CPD for a skill you already hold
Buying equipment, vehicles No Capital — claim via Annual Investment Allowance
Training to acquire a new qualification Generally No Viewed as capital expenditure on skills
Personal living expenses No Not exclusively for the trade
Rent for home office before trading Possibly Only the business proportion
Travel to research suppliers or locations Yes If wholly for the new business

Worked Example: Rachel’s Consultancy Launch

Rachel decides to launch a management consultancy in October 2026. In the two years before launch she incurs the following costs:

Date Expense Amount Qualifies?
Jan 2025 Accountant — business planning advice £600 Yes
Mar 2025 Market research reports £450 Yes
Jun 2025 Website design £1,200 Yes
Aug 2025 Professional indemnity insurance £800 Yes
Sep 2026 Business cards and launch marketing £350 Yes
Aug 2025 New laptop (£1,100) £1,100 No — capital (claim via AIA)

Total qualifying pre-trading expenses: £3,400

Rachel includes £3,400 in her first year’s Self Assessment return as business expenses. If her first-year profit before these is £18,000, her taxable profit becomes £14,600 — saving approximately £680 in Income Tax at 20%.

The laptop (£1,100) is claimed separately as capital expenditure under the Annual Investment Allowance — full deduction in year one.

Capital Expenditure: Not Pre-Trading Expenses but Still Deductible

Equipment, vehicles, and other capital assets are not pre-trading expenses — but they are not lost either. They qualify for capital allowances from the date you start trading.

Asset Treatment
Computer / equipment Annual Investment Allowance — 100% in first year
Van or lorry Annual Investment Allowance — 100% in first year
Car Writing Down Allowance — 18% or 6% depending on emissions
Fixtures and fittings Annual Investment Allowance — 100%

Key Rules to Remember

Rule Detail
Lookback period 7 years before trading starts
Treatment Deemed incurred on day 1 of trading
Legislation s57 ITTOIA 2005 (individuals); s61 CTA 2009 (companies)
Record-keeping Keep all receipts and invoices from the pre-trading period
Registration deadline Register for Self Assessment by 5 October after your first trading year

When Your Business “Starts Trading”

HMRC uses the point at which you first enter into contracts for the supply of services or goods as the start of trading — not when you register as self-employed or create a company. If you take on your first client informally before registering, the trading start date could be earlier than you think. Getting this date right matters for the seven-year lookback and for the basis period of your first tax return.

Record Keeping

Keep all receipts, invoices, and bank statements for pre-trading expenses. HMRC can ask to see evidence of any expense claimed on your return for up to four years after you file (longer in cases of carelessness or fraud). A simple spreadsheet listing each pre-trading cost, the date, supplier, and amount is sufficient supporting evidence.

See our Self Assessment guide, cash basis accounting guide, and self-employed expenses guide.

Sources

  1. HMRC — BIM46350: Pre-trading expenditure
  2. HMRC — Expenses if you're self-employed