Policies mitigating climate change provide a global public good but are also likely to imply local co-benefits where implemented. This may affect citizens’ preferences for what policy to implement as well as where to implement it. This aspect remains understudied despite its relevance for international climate negotiations, national policies, and the development of voluntary carbon credit markets. The results of a discrete choice experiment show that citizens in five countries (Denmark, France, Germany, Italy and Spain) have quite similar mean willingness to pay for carbon emission reductions and agree on the ranking of policies targeting different sectors. Specifically, policies targeting renewable energy use, are preferred over policies targeting industrial energy efficiency or carbon sequestration and biomass production in forests. Applying follow-up questions shows that concerns over co-benefits, notably air pollution, is linked to preferences for implementation in the home country. In the absence of co-benefits, citizens are indifferent or prefer policies implemented in other countries. Key policy highlightsCitizens in five European countries share preferences for climate change mitigation policies, though significant intra-national heterogeneity in preferences existPolicies targeting increased use of renewables are preferred over policies targeting improved energy efficiency in the industry.Citizens express preferences for policies implemented in their own country. This is associated with their perception of co-benefits. In particular, consideration of reduced air pollution as a side effect of investing in renewable energy and in energy efficiency in the industry are important determinants of preferences for national implementation of policies.Preferences for national co-benefits may both enhance policy acceptance and reduce willingness to support policies implemented in other countries. The latter aspect may reduce cost-effectiveness across countries but ease effort-sharing negotiations. Citizens in five European countries share preferences for climate change mitigation policies, though significant intra-national heterogeneity in preferences exist Policies targeting increased use of renewables are preferred over policies targeting improved energy efficiency in the industry. Citizens express preferences for policies implemented in their own country. This is associated with their perception of co-benefits. In particular, consideration of reduced air pollution as a side effect of investing in renewable energy and in energy efficiency in the industry are important determinants of preferences for national implementation of policies. Preferences for national co-benefits may both enhance policy acceptance and reduce willingness to support policies implemented in other countries. The latter aspect may reduce cost-effectiveness across countries but ease effort-sharing negotiations.