Car Insurance Averages for Full Coverage Policies. The average cost of full coverage car insurance varies between $850 and $2,000 a year. You can see that this is quite a range, which is why it is hard to estimate an actual average.There are so many things that go into figuring out car insurance rates, including where you live.f you move from one state to another and keep your same insurance company, you will probably notice a premium change, either up or down. One of the states that ranks highest in car insurance rates is New Jersey, where average annual premiums are around $2,500 per year.