Achieving a well-balanced innovation portfolio is an often advocated goal for R&D managers, but guidelines how to achieve this are scarce in the innovation and management literature. In this study, we investigate the effects that balancing R&D budget allocation between exploratory and exploitative innovation activities has on new product performance. Furthermore, we distinguish between product and process exploratory and exploitative innovation activities offering a new and highly relevant contingency perspective on the requirement to balance exploratory and exploitative innovation activities within a portfolio. In doing so, we integrate these two important dimensions of innovative activity in a framework that can help senior managers to decide how to allocate scarce R&D resources within an innovation portfolio to maximize returns. Based on a unique data set of objective, internal financial accounting data from strategic business units in the chemical industry, we found not only that new product performance is enhanced through the simultaneous pursuit of exploratory and exploitative innovation activities (i.e., they are complementary) which holds true for product and process innovation alike. But we are also able to show that in process innovation, exploration requires more funding to achieve maximal performance when compared to product innovation. An imbalance of exploration and exploitation has less severe consequences than in product innovation efforts. Our study design that is based on firm-internal R&D budget data allows R&D managers to directly compare their budget allocation practice with our findings that are derived from a wide range of business units in one of the main process industries. Furthermore, our results have important implications for the practice of R&D budget allocation, since they highlight how product and process innovation efforts differ with respect to their impact of the exploration–exploitation balance on new product performance relationship.