The 19-year-old has impressed with a number of positive displays since the beginning of the season, after Neil Taylor was ruled out with a broken leg in September.
However, Coleman is aware that he will face a selection dilemma once Taylor returns.
"Ben has done well, he's only 19," said Coleman. "Sometimes you get opportunities, sometimes you don't take them and sometimes you grab them with both hands and that's what Ben has done.
"He's grown in stature and confidence. Offensively he's getting better and better and he's got a great mentality and attitude to football and he's really done brilliantly.
"Neil just has to get fit and he can worry about where he's going to play after that. "Ben will know he's in good company when Neil gets fit, but all Neil has to focus on is getting himself ready and getting back."
Wales host Austria at the Millennium Stadium on Wednesday.