Vehicles that have more mileage are worth less money. This means finance lenders need to know how many miles you are likely to do over your contract. This is so they can work out how much to charge.
This information helps lenders avoid losing money on the vehicle. If you hand it back with higher-than-expected mileage, it won't be worth as much as they thought.
Mileage estimates apply to PCP (Personal Contract Purchase) and PCH (Personal Contract Hire). If you agree to a lower mileage allowance you will have lower monthly payments. Never underestimate your mileage. Lenders will charge a fee for every mile over your limit.