SR-22 isn't a type of car insurance. It's a certificate of financial responsibility that you may be required to carry after a driving violation like a DWI or at-fault accident. Your insurer files the SR-22 form to prove you have liability coverage. The form does not directly impact your rates, but violations that require SR-22 filing can increase your premiums significantly.
For liability-only coverage, Progressive and Mercury offer the cheapest SR-22 insurance for Texas drivers, averaging $601 and $609 annually, respectively. The two cheapest insurers for non-owner SR-22 insurance in Texas are State Farm and GEICO, which charge $429 and $899 per year.