Quick answer: Pre-trading R&D expenditure is qualifying R&D spend incurred before a company starts to trade. Under section 61 CTA 2009, spend from up to seven years before trading began is treated as incurred on the first day of trading, letting early-stage companies include historic development costs in their first R&D tax relief claim.
What is pre-trading R&D expenditure?
Pre-trading R&D expenditure is qualifying research and development expenditure incurred by a company before it starts to trade. Under section 61 of the Corporation Tax Act 2009, expenditure incurred in the seven years before trade commenced and that would have been deductible had the company then been trading is treated as incurred on the first day of trading. This allows early-stage companies to include historic development costs in their first R&D tax relief claim. The usual qualifying categories and rules apply.
How does HMRC define pre-trading R&D expenditure?
HMRC guidance on pre-trading expenditure in the R&D context is at CIRD81450 of the CIRD Manual and in the Business Income Manual at BIM46351. The statutory treatment is at section 61 of the Corporation Tax Act 2009.
What does pre-trading R&D expenditure look like in practice?
A deep-tech start-up spends £400,000 on qualifying R&D in the two years before it begins trading in May 2024. In its first accounting period to 30 April 2025, the company treats the pre-trading expenditure as incurred on 1 May 2024 and includes it in its first R&D claim under the merged scheme.
Worked example: turning pre-trading spend into a first-year credit
Continuing the example above, once the £400,000 of pre-trading R&D is folded into the company's first accounting period, it forms part of the qualifying expenditure base for the merged scheme's 20% above-the-line credit. £400,000 × 20% produces an £80,000 credit before tax adjustment - comparable to the 2023-24 average SME-scheme claim of roughly £85,400 (HMRC recorded £3.15 billion of SME-scheme relief across 36,885 claims that year). For a company that has not yet traded, capturing every eligible year of pre-trading spend in the first return is often the difference between a claim near the SME average and one well below it.
Why does the seven-year window matter for first-time claimants?
Because section 61 reaches back seven years, founders who spent several years building a product before earning revenue often assume the early costs are lost for tax purposes. They are not - provided the expenditure would have qualified had the company already been trading, and provided the first claim itself still falls inside the two-year claim window measured from the end of the first accounting period. First-time claimants should also check which categories of eligible R&D expenditure the pre-trading spend falls into, since staff costs, consumables and (from 1 April 2023) data and cloud costs are all treated the same way once folded into day one of trading. This is especially relevant for founders raising a seed round on the back of R&D already completed pre-incorporation trading, since the pre-trading credit can be modelled into cash-flow projections before the first CT600 is even due.
Related terms
Frequently asked questions
No. Pre-trading R&D expenditure is not claimed on its own - it is treated as incurred on the first day of trading and folded into the normal R&D claim attached to the company’s first corporation tax return (CT600). A quick eligibility check can show whether the accumulated pre-trading spend is likely to be substantial enough to justify the compliance cost of preparing a first claim.
Under section 61 of the Corporation Tax Act 2009, expenditure incurred in the seven years before trade commenced, that would have been deductible had the company then been trading, is treated as incurred on the first day of trading.
Yes. Once folded into day one of trading, pre-trading expenditure follows the usual qualifying categories, including staff costs, consumables and, from 1 April 2023, data and cloud costs, and the normal apportionment rules apply.
Yes. The first claim itself must still fall inside the two-year claim window measured from the end of the first accounting period, even though the underlying pre-trading spend can reach back up to seven years.