R&D tax relief calculator
R&D tax relief calculator: estimate first, evidence second
A calculator helps you decide whether a claim is worth taking further, but the final number depends on the company position and scheme rules.
Start with the R&D tax credit calculator for a quick value estimate, or the 30-second eligibility checker if you're not sure your work counts.
What to enter
Start with qualifying R&D expenditure, total relevant expenditure, whether the company is loss-making, and the Corporation Tax assumption. The better the cost estimate, the more useful the output.
What the output means
The result is a planning estimate. It helps with prioritisation, budgeting, and deciding whether to speak to an adviser before the Company Tax Return is filed.
Why the estimate can move
The final benefit can change when costs are excluded, apportionment is revised, ERIS conditions are not met, or evidence shows a project was commercial development rather than qualifying R&D.
Before you claim
- Check your claim deadlines: first-time claimers must notify HMRC within 6 months of year end.
- Prepare the Additional Information Form: HMRC wants it before the claim.
- Choose a specialist carefully: what a good review checks.
Important note
R&D tax relief depends on scheme rules, company facts, accounting periods, and HMRC evidence standards. Treat this page as research support, not tax advice.