I'm not really sure if there is a certain exercise that allows you to loose only chin fat. However, if you just start exercising in general, i can guarantee that you will loose chin fat, and other fat. So instead of looking for one particular exercise, you should really just start running, biking, doing crunches, or whatever. You will lose chin fat, and other fat.........what a plus!!!!!!!
There are certain exercises that you can do to help build your neck muscles. In doing so, your muscles will make your neck appear more taut and firm. But, if you have a large amount of neck fat, you may have to resort to liposuction or body wrapping to do the job.