They have three main horns on their face like most ceratopsians, one nasal horn, and two horns on the eyebrow area. The horns are short on some fossils, but longer on others, so it is possible that males posess the longer ones, and females posess the shorter ones.
They have a large, "heart shaped" frill that wouldn't have provided very much defense for the Chasmosaurus, but might have been bright and colorful, so it could have helped to attract mates.
One Chasmosaurus fossil had fossilized skin, that appeared to have had many large scales in evenly spaced rows among smaller scales, with five or six sides per knob. No information can be found out about the color of their skin, however.