Residential heating accounts for almost one-fifth of Germany’s final energy consumption. This report evaluates an extensive database of heating bills for buildings with two or more apartments, representing more than two-thirds of the total housing stock in Germany. Despite commitments to pressing climate targets, the rate of thermal upgrades of the existing housing stock has remained low since the turn of the 21st century, while heating energy demanded per square meter by private households has been on an upward trend since 2015. This is an alarming development with respect to the 2050 climate goals for the buildings sector. An additional set of policies are therefore necessary to achieve the yet-unrealized reductions in energy consumption in the building sector. These include, for example, tax incentives for top-end retrofits that have been discussed for more than a decade and policies targeting household behavior such as providing consumers with more frequent and timely information.