The lease payment only covers the depreciation and sales tax for the period of the lease term (3 years is a common lease term). And the come-on leases often have low mileage limits (like 10,000 miles per year). If you exceed that mileage expect to pay 20-25 cents per mile at the end of the lease. Or if you want realistic mileage limits, you can add it to your monthly payment (at the rate of 15-20 cent per mile typically). Lastly lease programs are often heavily subsidized by manafacturer to move vehicles. Just some of the reasons for the lower lease payment (vs. purchase loan payment).