I was recently in an accident with an at fault driver. So far I've had one surgery and getting ready to have a second. My medical bills are already starting to pile up. I live in Tennessee and was wondering how underinsured policies work. My policy is 100,000/300,000. Say for instance her policy is the same as mine, would I only be able to collect up to 100,000 or would I be able to make a claim on my underinsured for 100,000 for a total of 200,000. I'm not saying my case would require that much but I don't understand how all of this works. Luckily I have never had to deal with this before.