Last reviewed 27 August 2026 · Based on current GOV.UK towing guidance and practical caravan-matching experience.
How to calculate the 85% figure
Multiply the car’s kerb weight or mass in service by 0.85. The answer is an indicative caravan MTPLM ceiling under the 85% guide.
For example, a car with a confirmed kerb weight of 1,600kg gives an 85% guide figure of 1,360kg.
- 1,600kg × 0.85 = 1,360kg
- Compare the answer with the caravan MTPLM, not its empty weight
Is 85% a legal towing limit?
No. The 85% ratio is guidance, not UK law. A combination below 85% is not automatically safe, and a combination above it is not automatically illegal. The vehicle manufacturer’s limits, actual loading, gross train weight, licence entitlement and the full outfit still need checking.
What happens between 85% and 100%?
Some experienced towers use combinations above the 85% guide while remaining within every legal and manufacturer limit. Greater care, experience and attention to the complete outfit are important. A caravan should not be selected from the ratio alone.
Stability depends on more than the ratio
- Correct nose weight within every applicable limit
- Sensible loading with heavy items low and near the axle
- Tyre condition and correct pressures
- Car and caravan suspension condition
- Speed, weather, road conditions and driver input
Official sources and further checks
Rules and vehicle limits can change. Before towing, check GOV.UK towing-with-a-car guidance, GOV.UK towing weight and width limits and the documentation supplied by your vehicle, towbar and caravan manufacturers.