Plug-in hybrid cars type-approved according to the new WLTP emit on average about three times more CO₂ in real-world driving if they are registered by a private owner. Those registered as company cars on average emit five times the emissions estimated by the official test procedure. In comparison, the average combustion engine car exhibits a real-world gap of “only” around 15 % for CO₂ in WLTP. From 2025 onwards, the so-called utility factor for plug-in hybrids will be revised, thereby leading to more realistic CO₂ emission values reported to consumers and authorities.