For the first time during Western Europe’s lengthy diesel decline, diesel share of new car sales dipped below 10% in September (the provisional figure, unlikely to change much, is 9%). But a glance at the YoY curve in the chart above shows that by that measure, a poor September diesel share isn’t too unexpected.
The underlying downward trend remains, but September car sales are skewed to the UK for vehicle registration plate reasons, amplifying that country’s impact on diesel share – diesel share in the UK is now sub-5%. YoY decline at the monthly level remains between 2 and 4 percentage points, as it has done since April of this year.
In all, 100k diesel cars were sold in the region in September, a decline of 20k over September 2024. To date this year, the diesel market has lost 250k, with Q1-Q3 2025 sales at 1 million units exactly. Though Germany didn’t see its September diesel market lose too much ground versus a year earlier, it has contributed most to the YTD loss (82k of the 250k decline – one third). That said, Germany still accounts for 43% of the region’s diesel car sales so far in 2025. Italy and Germany combined made up 61% of this year’s diesel car market.
This article was first published on GlobalData’s dedicated research platform, the Automotive Intelligence Center.
