Go for Progressive...it might not always be the cheapest but has the best service for sure...Don't get lured by some cheap small companies....they are good only when you are paying for it...however, if you run into any mishaps (which is when you need them), they show the cheap nature...

You can never say one insurance company is cheaper than the other...because the rates for each company vary by the risk factor...A company can be cheap for one type of risk (say for example young drivers) and at the same time can be the most expensive for other types of risks (say for example females). As a customer, your job is to find the company that is the cheapest for the type of risk similar to you. The best way to do that is only by getting quotes from as many companies out there. Progressive could still be a good website for this purpose. You can get your quote from Progressive as well as many other top companies.

Here are few things that can generally lower your rates.

1. If your roomate/GF whoever lives with you has a car, try to get more than one car in a policy. This way you'll get a multicar discount. Additionally, you will also be splitting the fixed acquisition cost (which companies acquires per policy) between the two cars in a policy.

2.Credit score- While insurance credit scoring is slightly different than the regular credit scores, it does affect your rates. If you don't have a good credit score, try getting one of your friends with a better score as the PNI (primary name insured) in the policy. They only review the credit score of the PNI.

 3.Drive safe- violations, points, speeding tickets in your motor vehicle report increase your rate. If you have a bad driving record, try including someone with a better driving record in the policy. While most companies rate on the worst drivers, there are still some companies that average the drivers in the policy, in which you'll benifit by adding a better driver. 

4. Proof of prior insurance- Companies have statistically proven that perple with no lapse in insurance are better drivers. Thus, their rates are better. usually they ask for 3 years of continious insurance. However, I have seen that they only ask for proof of your most recent policy. If you don't have 3 years of insurance but have at least 1 term of insurance, say you have it for all 3 years. Some companies do verify for al 3 years. However, you have nothing to lose if you can't provide the proof.

5. True, that married people get a lower rates than singles. Although it is considered an insurance fraud if you fake it, I don't think many companies verify that you are married.

6. Older you are better your insurance rates. Same is true with more years of driving experience. It is good to get a liscence as soon as you can even if you don't have a car yet.

7. There are different discounts offered by different companies such as education, home ownership, good student, etc. While most verify home ownership, eligibility for education, good student discounts are not verified by most companies.

9. Female drivers have cheaper rates. If you have females in the policy make them the PNI of the policy. Always make the better driver the PNI.

10. If you have money, pay in full. That will be cheaper as well that paying in installments.

11. Lower limits, obviously, are cheaper. If you have a vehicle with model year older than about 5 years it might not be worth buying the Collision and Comprehensive coverages. Even if you have to, increase the deductibles so that it is a little cheaper. $500/$1000 should be a good choice.

12. Insurance rates vary by territory (your zip code. If you frequent two zip codes, use the cheaper one as your garazing zip code.

Again, the best way to get a lower rate is by getting as many quotes from different companies.