R&D Tax Credits + Advance Assurance: Turning Innovation Spend Into Predictable Cash

R&D tax credits are one of the most generous innovation incentives in the world. They are also one of the most poorly claimed. Founders either over-claim and get clawed back, under-claim and lose 5-figure sums, or never claim at all because they think 'we are not really doing research'.

What actually counts as R&D

HMRC's definition is wider than founders assume. You qualify if you are seeking an advance in science or technology by resolving scientific or technological uncertainty that a competent professional in the field could not readily deduce. In practice, this includes most original software, hardware, AI/ML, algorithms, integrations and process engineering — not just lab work.

What you can claim

• Salaries (and employer NI/pension) of staff working on R&D, time-apportioned.
• Subcontractor costs (rules differ — typically 65% of the cost is qualifying).
• Software licences directly used for R&D.
• Consumables and utilities used in the R&D process.
• Cloud computing and data costs (added in the 2023 reforms).

The new merged scheme

From April 2024, SME R&D and RDEC merged for most claimants. Loss-making R&D-intensive SMEs (R&D spend more than 30% of total expenditure) get an enhanced rate. Everyone else gets the merged scheme rate — equivalent to roughly 15–16.2% of qualifying spend net of tax.

Advance assurance — the bit founders miss

First-time claimants with under £2m turnover and fewer than 50 employees can apply for advance assurance — HMRC pre-approves your R&D claim methodology before you submit. It removes the guesswork, cuts enquiry risk, and lets you forecast the cash with confidence.

Why it matters for cash planning. Without assurance, your R&D claim is a 'maybe' for 6–12 months. With it, you can model it as a predictable receivable and plan runway accordingly.

Common claim mistakes

• Claiming routine development as R&D — HMRC has aggressively challenged this since 2023.
• Poor technical narratives — 'we built features' is not a qualifying explanation.
• Missing the additional information form (mandatory since August 2023) — claim invalid without it.
• Including ineligible directors' dividends as 'salaries'.
• Not separating qualifying vs non-qualifying time per project.

Realistic process

Advance assurance: 4–8 weeks. Annual claim filing: alongside or after your CT600. Cash refund: typically 4–8 weeks after submission for SMEs. We work with specialist R&D accountants to scope qualifying activities, write the technical narrative and file the claim.