The global growth of the consumption of non-wood forest products (NWFPs) is evident due to the current trends in lifestyle and consumption. Alongside the increased popularity and commercial use of NWFPs, their yields are also more often taken into account in forest management planning. Empirical yield models recently developed for different NWFPs enable forest managers to include their predicted yields in multi-objective optimization. However, knowledge on the synergies and trade-offs between timber production and different NWFPs is scanty. In this study, we analyzed these relationships through correlation matrices and production possibility frontiers in two case study forest holdings from Finland. A large number of Pareto optimal forest holding level plans were produced by multi-objective optimization and used to analyze trade-offs and synergies. Empirical yield models for 12 NWFPs, representing different berries, mushrooms, and tree-based products, were utilized in the analyses. The results revealed synergies and possibilities for joint-production for NWFPs, but also trade-offs between NWFPs and timber production. NWFPs often had a negative correlation with cutting removals, with the only exception being cowberry. Despite the overall negative correlation, the maximum yields of NWFPs called for some cuttings. Negative correlations with the net present value of timber production were weaker. The results are valuable when the aim is to diversify the use of boreal forests and open avenues for truly multi-objective decision support services to facilitate the decision making of forest owners.