The European Union (EU) does not have a common forestry policy but EU policies can indirectly affect the forest sector. This study departs from the EU “Fit for 55” package of legislation and uses a forest sector model to simulate and analyze three responses in the Swedish forest sector (2020–2100) to policy initiatives addressing climate change and biodiversity: (i) increasing the area of set-asides with 50%; (ii) prohibiting harvest of old forest (>120/140 years of age); and (iii) extending the minimum allowed age for final harvest with 30%. Results indicate that, while all three responses can reduce net carbon emissions compared to business-as-usual, extension of the minimum allowed age for final harvest reduces emissions the most. In general, the effects on net carbon emissions are highly correlated with the level of harvest. Increasing the area of set-asides and prohibiting old forest harvest help preserve old forest better than both business-as-usual and final felling age regulation. Longer-term results are uncertain as policies and technology development can radically change biomass use, product portfolios and displacement effects.