R&D Tax Credit Calculator UK

R&D Tax Credit Calculator UK

Estimate relief under the merged R&D expenditure credit scheme or enhanced R&D intensive support (ERIS).

Select the scheme you want to estimate.
Enter expenditure that meets the tax definition of qualifying R&D.
Required for the merged scheme net-credit estimate.
Required only for ERIS; use the post-enhancement unrelieved loss.

How to use the R&D Tax Credit Calculator UK

Choose the merged scheme or ERIS and enter qualifying R&D expenditure. For the merged scheme, also enter the Corporation Tax rate applied to the taxable expenditure credit. For ERIS, enter the unrelieved trading loss after the additional R&D deduction.

Important: this is a simplified estimate, not tax advice or a claim calculation. Confirm eligibility, qualifying expenditure and claim restrictions with a suitably qualified UK tax adviser.

Rates used by the calculator

Scheme Simplified calculation
Merged scheme RDEC 20% gross taxable expenditure credit; estimated net benefit deducts entered Corporation Tax
ERIS 86% additional deduction; surrenderable loss is the lower of 186% of qualifying spend and entered unrelieved loss; credit rate is 14.5%

Merged R&D expenditure credit

For accounting periods beginning on or after 1 April 2024, the merged scheme provides a taxable expenditure credit. The calculator first applies the 20% credit rate and then deducts Corporation Tax at the percentage you enter to show an estimated net benefit.

Enhanced R&D intensive support

ERIS is for eligible loss-making R&D-intensive SMEs. The additional deduction is 86% of qualifying expenditure. The payable credit is 14.5% of the surrenderable loss, limited in this calculator to the lower of enhanced expenditure and the entered unrelieved loss.

Official HMRC guidance

HMRC explains the eligibility rules, accounting-period conditions, intensity requirement and claim calculations in its merged scheme and ERIS guidance. Check the current guidance for your accounting period before preparing a claim.

What this estimate does not include

The calculator does not test whether a project advances science or technology, classify individual costs, apply overseas-contractor rules, calculate the PAYE cap, offset tax liabilities or complete the additional information form and Company Tax Return.

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Frequently asked questions

What rate does the merged R&D scheme use?

The calculator uses a 20% gross expenditure credit, which is taxable.

What rate does ERIS use?

It uses an 86% additional deduction and a 14.5% payable credit on the surrenderable loss.

Can every loss-making SME claim ERIS?

No. The company must meet the relevant SME, loss-making and R&D-intensity conditions for its accounting period.

Does the calculator decide which costs qualify?

No. It assumes the entered expenditure is qualifying and does not test individual project or cost eligibility.

Is the result the amount HMRC will pay?

No. Tax offsets, caps, restrictions and claim-specific facts can reduce or change the final benefit.



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