The Czech R&D tax deduction is one of the country's most important tax incentives for innovative companies, but it is also an area where weak documentation can undermine an otherwise legitimate claim. Changes effective from 1 January 2026 adjusted both the mechanics and timing of the deduction.
The Financial Administration specifically highlights a new 'odpočtový celek', or deduction-unit concept, and a longer period over which eligible deductions can be applied.
The five-period window reduces some timing pressure
The 2026 rules extend the period for using R&D deductions to five tax periods and allow more flexible movement of deductions into later periods. That can matter for companies whose tax base fluctuates or whose R&D investment arrives before profitability.
The change does not remove the need to establish that the underlying activity qualifies. Tax treatment follows the statutory R&D rules, not the company's internal label for a project.
Documentation remains the central risk
A software feature, production improvement or engineering project is not automatically qualifying R&D merely because it involves technical work. The company needs evidence of the research or experimental-development element and a defensible link between qualifying costs and the project.
For technology companies, that means separating routine implementation, customer customisation and maintenance from work that genuinely addresses technical uncertainty.
Why the deduction matters strategically
The incentive can reduce the after-tax cost of engineering and research carried out in Czechia, making it relevant to both Czech-owned firms and multinational R&D centres.
For location decisions, however, the tax deduction should be read alongside payroll costs, labour availability, grants and the practical ability to hire specialised technical staff.