Revenue Commissioners
Knowledge Development Box (KDB)
aka KDB, Section 769G
Effective 10% corporation tax rate (raised from 6.25% under Finance Act 2022) on profits from qualifying intellectual property developed through R&D activity in Ireland.
Effective 10% CT on qualifying IP profits (vs standard 12.5%)
Last reviewed May 2026
What this scheme funds
The Knowledge Development Box is Ireland's OECD-compliant patent box. Profits attributable to qualifying intellectual property assets (patents, copyrighted software, plant-breeders' rights and supplementary protection certificates) are taxed at an effective 10% rate (up from 6.25% for accounting periods commencing on or after 1 October 2023 under Finance Act 2022), against the standard 12.5% corporation tax rate. The relief is calculated using a modified nexus formula that links the qualifying profit to the proportion of R&D actually performed in Ireland (or in the EEA) by the claimant company, so the benefit narrows quickly if R&D is sub-contracted heavily outside the group. KDB is most often paired with the R&D Tax Credit: the credit lowers the cost of the R&D itself, and KDB lowers the tax on the profits the resulting IP throws off.
Application window
Claimed via the corporation tax return (CT1)
Who can apply
- •Irish tax-resident company carrying out qualifying R&D in Ireland or EEA
- •Owns or co-owns a qualifying IP asset created from that R&D
- •Tracks R&D spend on the asset on a per-asset basis (or per-asset family for SMEs)
- •Files the KDB claim with the corporation tax return (CT1)
How it typically funds software
- •SaaS companies that hold the copyright in their codebase and develop materially in Ireland
- •Combine with R&D Tax Credit for compounding benefit on both the cost and the return on IP
Worth knowing
KDB documentation requirements are heavy - track qualifying R&D spend by asset from day one. Retrospective reconstruction rarely survives a Revenue audit.
Software categories this can fund
Related grants
Revenue Commissioners
R&D Tax Credit
30% refundable tax credit on qualifying research and development expenditure, claimed via the company's annual corporation tax return.
Enterprise Ireland
Innovation Voucher
EUR5,000 voucher that funds a small business to work with a registered higher-education or research institution on an innovation question.