Minor Car Accident

Hello, in need of a little help/advice.

I recently had a minor incident, where I've clipped another car, denting his rear panel but only scuffing my front bumper. I'm not bothering to claim for my own damage as it's only cosmetic and I'll sort it myself at a later date. Now I'm to blame (unfortunately) for the incident. If the car I've damaged claims off my insurance for his car repairs, will I actually have to pay anything? e.g. my excess? Oh, an I'm fully comp insured.

Thanks in advanced.