SR-22 isn't a type of car insurance but a certificate of financial responsibility you might need after a moving violation. You or your insurer files it to prove you have liability coverage. Though the form doesn’t raise your rates, the violations requiring an SR-22 can increase your premiums.
For minimum coverage, State Farm offers the cheapest SR-22 insurance at $413 per year, followed by Farmers at $578. For non-owner SR-22 insurance, State Farm is also the lowest at $303 and GEICO at $458.