Coyle has committed himself to Leeds until the summer of 2019, extending a deal which was due to expire at the end of this season.
The talented right-back, who turned professional with the club in 2014, has come to prominence in the past 18 months, making 17 competitive appearances and featuring five times this season.
He is currently on the injury list after suffering knee ligament damage in a recent League Cup win over Norwich City.
The defender is expected to be absent for up to 12 weeks but Leeds have softened the blow by tying him to an improved deal.
Coyle said: “I’ve had some bad news with the injury so this is definitely good news. You’re always fighting for that next contract so for it to be done is a positive.
“I feel when I’ve broken through into the team I’ve taken my chance and done well so it’s nice to be rewarded.”
“I’ve been here since the age of seven so the thought of not being here is a daunting one. I’ve come on leaps and bounds this season, it’s great to be coached under Garry Monk and we’re looking up from here.”