Impact of sufficiency on achieving the EU's 2030 and 2050 greenhouse gas emissions targets

• Lifestyle sufficiency can scale climate mitigation in the EU. • Delta and factor metrics give complementary sufficiency estimates. • Dietary shifts and less air travel cut GHG emissions most (up to 650 Mt CO2e by 2050). • EU countries show unique adoption patterns of sufficiency measures. • Sufficiency narrows—without closing—the NECP gap, complementary policies are needed. The European Union (EU) is legally bound to achieve climate neutrality by 2050, but current greenhouse gas (GHG) trajectories indicate that this target may be missed. While technological efficiency improvements and renewable energy deployment are central to climate strategies, lifestyle-based sufficiency measures remain underexplored. This study assesses the GHG reduction potential of six energy sufficiency measures across five EU Member States—Denmark, France, Germany, Italy and Latvia—and evaluates their contribution to narrowing policy-relevant emissions gaps in National Energy and Climate Plan (NECP) trajectories. Using the MARIO (Macroeconomic Assessment of Resource Inputs-Outputs) framework, we apply a scenario-based modelling approach comparing sufficiency scenarios against both linear projections and the European Environment Agency’s “With Existing Measures” (WEM) baseline. Emission reductions are calculated using delta (absolute difference) and factor (relative ratio) metrics to establish upper and conservative bounds. Sensitivity analyses assess baseline selection. Sufficiency measures, particularly dietary change and reduced aviation demand, show the highest mitigation potential. By 2030, the six measures reduce emissions by up to 170 Mt CO 2 e across the five countries, increasing to 650 Mt CO 2 e by 2050. Relative to 1990 levels, this corresponds to reductions of 0.9–4.4 % by 2030 and 1.1–16 % by 2050, depending on methodological boundary conditions. While sufficiency alone does not achieve net zero, it materially narrows the emissions gap relative to NECP trajectories, particularly in hard-to-abate sectors such as food systems and aviation. Sufficiency therefore offers a bounded but policy-relevant complement to technological decarbonisation and warrants systematic integration into EU climate governance frameworks.