McKay has put pen to paper on a new deal which will see him remain at Rangers until May 2018.
The 21-year-old winger has taken to Twitter to express his joy at committing his long-term future to the Glasgow giants.
Seems like it's taken ages but these things usually do. Delighted to sign extension and now kick on for season. Thanks for all the messages— Barrie McKay (@BarrieMcKay) February 15, 2016
McKay is a promising young player and has established himself as an important member of Mark Warburton’s team. The youngster has scored six goals in 33 games for Rangers so far this season.
The Scotland Under-21 has played a total of 78 times for the Scottish club, after making his first start against Brechin City in July 2012 at the age of 17.
Rangers are at the top of the Scottish Championship table at the moment with 60 points from 24 matches. Warburton’s side are eight points clear of second-placed Hibernian, who have a game in hand.
The Gers will return to action on Tuesday evening when they take on Kilmarnock away from home at Rugby Park in the Scottish Cup fifth-round replay.