The R&D tax incentive and ZIM both support research and development, but they follow different funding logics. The R&D tax incentive is a tax-based R&D support scheme handled through the BSFZ certificate and the tax office. ZIM is a classical grant programme for innovative R&D projects by SMEs. For the R&D tax incentive, the main question is whether the project technically qualifies as R&D under the Research Allowance Act. For ZIM, level of innovation, market relevance, exploitation plan, work plan and programme fit are also important. The R&D tax incentive can be attractive for internal R&D projects, even if no classical grant application was submitted before project start. ZIM is more strongly linked to approval, project duration, drawdown of funds, reports and proof of use. Applicants need to decide whether the project should be treated mainly as tax-based R&D support or as an approved grant project. In practice, both programmes can be useful, but cost separation, double funding and procedural logic must be checked carefully.