That depends on many factors. Each case is unique.
If you are injured, you should never settle before you have reached “maximum medical improvement”. If you have not gotten as well as your doctors can get you, you should not settle.
If you have a permanent injury, it’s critical to have an understanding what your future medical needs and limitations will be. In order for you to get a fair settlement and for me to present your case to an insurance company or a jury, I research your condition and meet with your main doctors and therapists to get hard evidence of the effect your injury will have on your life.
If suit is filed, there are rules to allow both sides to gather information before trial so they can assess and prepare for mediation and trial. Your lawyer needs to be skilled in knowing how to get all the information from the other side that the law allows. That can take time, and some opponents fight to keep from disclosing some evidence.
The court sets time limits and schedules all trials. The schedule for your case may depend on the county or court where it’s filed and the number of cases pending in that county or court.
I always want to move my clients’ cases as fast as possible without sacrificing the chance to best develop each case. Most cases take several months to resolve. If the insurance company for the responsible party forces you to file suit, you will probably wait 12 to 18 months before trial.