Your letter should include a concise factual summary of the accident, an overview of your damages, your settlement demand, and not much more. Sample of a Cash Settlement Letter.Below is a sample demand letter for an auto accident case. I'm about to start writing a settlement deman letter to Geico for a Rear end Collision i was in. The other driver accepted full repsonibility as well as geico. Don't make your letter too long. A car accident settlement letter is a formal written communication aimed at resolving a dispute amicably before proceeding to litigation. How to fill out the Settlement Demand Letter for Car Accident Claims? This is a sample settlement demand letter for a car accident claim involving soft tissue injuries. " The pain in my head and neck felt like I was being stabbed with a knife.