Glossary
WLTP Test Cycle
Direct Answer / TL;DR
What is WLTP Test Cycle?
The Worldwide Harmonised Light Vehicle Test Procedure (WLTP) is the official EU and UK fuel economy test that replaced NEDC in 2017–2019. It uses more realistic speeds, durations, and equipment options to produce fuel consumption figures closer to real-world driving.
Why does it matter for UK drivers?
WLTP was introduced to close the credibility gap that had grown with NEDC figures. The test is more demanding: it covers 14 miles (vs NEDC's 6.8 miles), uses a maximum speed of 81 mph (vs 75 mph), and has a longer test duration of 30 minutes. Crucially, WLTP also accounts for optional equipment — the air conditioning system, panoramic roof, and other factory options all affect the tested figure.
For most cars, WLTP figures are 10–25% lower than the NEDC figures they replaced. A car previously rated at 50 MPG (NEDC) might appear as 41–44 MPG (WLTP). This can look like efficiency got worse when in reality the measurement became more honest.
All new cars registered in the UK from 2019 onwards must publish WLTP fuel consumption figures. Older cars still carry NEDC figures in databases and documentation.
WorthThePump uses WLTP data where available (from the VCA dataset and DVLA VES API) and applies a 12% real-world penalty. For NEDC-rated vehicles a larger 20% penalty is applied, reflecting the greater gap between NEDC lab results and real roads.
For drivers comparing cars on a like-for-like basis, always compare WLTP to WLTP. Comparing a new car's WLTP figure to an older car's NEDC figure will make the older car appear more efficient than it actually is in practice.
Related terms
Further reading
Now you know what WLTP Test Cycle means —
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