The England international is in the last year of his contract and has been linked with the likes of Arsenal, Liverpool and Manchester City.
Coyle insists no bids have been received for the 25-year-old and it is business as usual for the player.
The Wanderers boss pointed to Cahill's performance in last weekend's opening-day 4-0 victory at QPR, where he scored the first goal with a stunning 20-yard strike, as evidence of the centre-back's level-headedness.
"There is no foundation to the speculation and I have said to Gary there is nothing to be distracted about," said Coyle.
"He has to focus on what he does for Bolton; he gets well paid by the club and has a great contract and we have invested a lot of money in him after buying him from Aston Villa.
"He has shown that focus with his performances. If there was something concrete to happen then Gary would be the first to know.
"He knows the way I work as a manager, the relationship I have with him and you saw last week how focused he was.
"Aside from his defensive performance what he adds at set-plays and moving forward and the goal he scored is all credit to Gary Cahill and long may it continue.
"I have said before Gary has, I believe, the feet of a centre-forward even though he operates at the back.
"It was a world-class strike from a world-class player in the making."
Coyle is still trying to bring in players before the close of the transfer window with Liverpool striker David Ngog and Shaun Wright-Phillips, whose current club Manchester City visit the Reebok Stadium on Sunday, the ones continually linked.
However, the Scot admitted the problem was not identifying players he wanted to sign but getting those targets to accept Bolton's financial terms.
"I think it is fair to say we are chasing one or two targets but I don't have anything concrete," added Coyle.
"I am always hopeful. I target players who I believe can improve the squad but it is not always as simple as saying 'I want that player, in you come'.
"There has to be a willingness from the player who wants to hear what the project is and then there is the finance, both with clubs and players, and that is where we are now with one or two."
One new signing who is set to join the Bolton squad for Sunday's match is Tuncay Sanli, who is expected to finalise his work permit and travel fromm Germany in time to be included.
Source: Team Talk
Source: Team Talk