Misfuel Incident Trends in New Zealand: What 2025 Taught Us
A review of misfuelling patterns in New Zealand through 2025 reveals consistent seasonal peaks, vehicle category trends, and regional hotspots. Here is what the data shows.
2025 in Review
Misfuelling incidents tracked through EEK Mechanical's call records and the preliminary data flowing into the NZIFDA National Misfuel Register show consistent patterns across New Zealand in 2025. Total incident volume increased approximately 12% year-on-year, consistent with growth in the diesel fleet and increased road travel volumes following the post-COVID normalisation of travel patterns.
Seasonal Peaks
The highest incident months in 2025 were January (summer holidays), July (school holiday period, cold weather), October (school holidays, spring road trips), and December (Christmas travel). The lowest incident months were typically February and August — consistent with reduced travel volumes outside major holiday periods.
Vehicle Category Shifts
A notable trend in 2025 was a measurable increase in misfuel incidents involving newer diesel SUVs — particularly the Toyota Fortuner, Ford Everest, and Mitsubishi Outlander diesel. These vehicles are increasingly prevalent in family and lifestyle fleets, driven by a wider range of household members who may not have the fuel type as well-established in their fuelling habits as the primary owner.
Looking Ahead
2026 brings new complexity in the form of increasing PHEV and mild hybrid diesel penetration, continued growth in the diesel SUV segment, and the transition of some corporate fleets toward EVs that will create cross-contamination risk for staff driving both fuel-powered and electric vehicles from the same motor pool.
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