Unfortunately, there's no way to tell how long it'll take to find a fair back injury settlement in California. Also, in simple situations with no complex liability problems, it may take several months for the insurer to want to finalize a settlement agreement. Unfortunately, there's no way to tell how long it'll take to find a fair back injury settlement in California. Also, in simple situations with no complex liability problems, it may take several months for the insurer to want to finalize a settlement agreement.