Households in Germany, particularly those with natural gas and pellet heating, faced a significant increase in their heating costs in 2025. This is according to the recently published German Heating Index for 2026. The study, a joint publication by co2online, the German Tenants' Association, and the Bauherren-Schutzbund e.V. (BSB), highlights that fossil heating systems pose a substantial cost risk in the long term.
The analysis is based on an evaluation of numerous real heating cost statements and allows for a precise comparison of individual heating energy consumption and associated costs with those of similar properties. For an average single-family home of 130 square metres, heating costs between EUR 1,260 and EUR 2,145 were recorded in 2025, depending on the installed heating system.
The development of heating costs for gas and oil heating systems is significantly influenced by anticipated increases in CO2 costs, higher network charges, and the so-called 'Bio-Treppe' (bio-staircase). These factors could lead to costs more than doubling by 2045. In contrast, the study points out that switching to renewable energies in a single-family home can already generate an average savings potential of around EUR 1,000 per year today.
Potential for Cost Reduction
Around 90 per cent of German households have opportunities to reduce their heating costs. Henrik Fork-Weigel, Managing Director of the Bauherren-Schutzbund, underlines the Heating Index's statement that a significant reduction in heating costs is achievable for many households. He advises owners considering modernisation to first accurately determine their own consumption and identify the causes of potentially high energy demand. A well-conceived modernisation concept that coherently coordinates the building envelope, heating demand, and heating technology is essential to avoid misguided investments.
The Heating Check as an Analysis Tool
For property owners, the Bauherren-Schutzbund now offers co2online's Heating Check via its own website. This digital tool allows individual consumption and cost data to be compared with those of similar buildings. It provides an indication of whether one's own consumption is to be classified as low, average, or conspicuously high. Mr Fork-Weigel emphasises that the Heating Check does not replace individual expert advice or detailed planning, but it can offer a valuable basis for assessing one's own consumption and thus for further modernisation decisions.
