Skip to content
Unclaimed
Discovery tool, not advice. Every figure is the published rule, not a decision on your case.
Tax credits

R&D expenditure credit (RDEC) for accounting periods beginning before 1 April 2024

R&D expenditure credit (RDEC) — pre-April 2024 scheme

Status

Closed for now

The funder has not said when this reopens.

Closed
Amount
Not published

Credit of 20% of qualifying costs incurred 1 April 2023 to 31 March 2024 (13% for 1 April 2020 to 31 March 2023). Only relevant now for late or amended claims covering accounting periods that began before 1 April 2024; superseded by the merged RDEC scheme.

Funder

HM Revenue & Customs

public · national

Deadline: Closed — Applies only to accounting periods beginning before 1 April 2024. New periods must use the merged RDEC scheme or ERIS. Included because amended/late claims for earlier periods are still possible.

Your odds
Not published

This funder does not publish a success rate. We rank it using the rate observed across similar programmes and label it as an estimate rather than implying we know.

Effort
moderate

Moderate — a form and supporting documents.

Who can apply

SMEs used this scheme where work was subcontracted to them, where they received notified State Aid, or where costs were subsidised (e.g. by a grant).

How to apply

  1. Confirm the accounting period began before 1 April 2024 and you fall in an eligible category (large company, or SME claiming subcontracted, state-aided or otherwise subsidised work).
  2. Claim through the Company Tax Return with the additional information form.

What you will need

Related reading: How grant deadlines actually work · R&D tax credit vs. grant: the difference that changes your claim

Apply on the funder's site

Source. https://www.gov.uk/guidance/corporation-tax-research-and-development-tax-relief-for-large-companies

"The tax credit is worked out as a percentage of your qualifying R&D costs. The rate on costs from: ... 1 April 2023 up to and including 31 March 2024 is 20%"

Verified on 14 August 2026

Source: www.gov.uk

Similar programmes

Enterprise Investment Scheme (EIS)

Open continuously

HM Revenue & Customs

Seed Enterprise Investment Scheme (SEIS)

Open continuously

HM Revenue & Customs

Enhanced R&D intensive support (ERIS) for loss-making R&D intensive SMEs

Open continuously

HM Revenue & Customs

Merged R&D expenditure credit scheme (merged RDEC)

Open continuously

HM Revenue & Customs

Patent Box

Open continuously

HM Revenue & Customs

R&D tax relief (merged RDEC scheme and Enhanced R&D Intensive Support)

Status not published

HM Revenue and Customs

Paid, separate from Unclaimed

Want a human to review your application?

Involve Consulting can help — a paid expert-review service run by the same person behind Unclaimed, entirely separate from this free check. A flat fee, agreed up front; never a cut of what you receive.

Talk to Involve Consulting