The centre-back turned 34 in the summer but has revealed the knee injury that stunted his progress last season has made him call time on his playing days.
Confirmation of his decision comes on the eve of the new Championship season with Ryan Mason’s Baggies preparing to host Blackburn on Saturday.
Bartley’s 16-year professional career ended with seven years at The Hawthorns, where he clocked up 232 appearances for Albion. He was the longest-serving senior player on the club’s books having triggered a one-year contract extension due to appearances last term.
He netted 15 times for the club and played a key part in winning promotion to the Premier League in the 2019/20 campaign.
The defender revealed, despite his best intentions at recovering from the setback, a knee injury has forced his decision. Bartley was in Austria with his Baggies team-mates for pre-season this summer but has not trained with his colleagues.
Bartley said: “I am fortunate to have represented some outstanding clubs during my career and Albion holds a particularly special place in my heart.
“Unfortunately, a knee injury I picked up during last season has led me to make the difficult decision to hang up my boots, despite my best efforts to rehabilitate from it.
“I consider myself incredibly lucky to have played the game I love, and it is the highs and lows of football that have helped make me the man I am today.
“I would like to place on record my thanks to all at the club for their support during my seven years here. The club is fortunate to have some outstanding people working at all levels and I’m lucky to have established some special friendships along the way.
“I’ll continue to support Ryan Mason and the lads and don’t plan on being a stranger at The Hawthorns – a special place that I will always be fond of.
“I’d also like to thank the fans for their amazing support throughout the years. My family, too, are now all fans, especially my two little girls and I’m hoping we will all be back very soon to say thank you for everything. This club will always be part of my life.”
Bartley, who is Stockport-born and came through the youth ranks at Bolton and Arsenal, has been the club’s vice-captain for an extended period.
He underwent an operation on his knee earlier this year and Albion managed him through the period. The defender was no longer in a position where he could play regularly games pain-free, but remained a regular in the side from the beginning of March for the final two months of the season.
The veteran clocked up 407 senior appearances across his career with spells at Sheffield United, Rangers, Swansea, Birmingham City and Leeds.
It was against Blues in 2022 where Bartley’s time with the Baggies hit a low as he was hauled off to jeers and and ironic cheers by then-boss Steve Bruce in a disastrous home defeat, in which visiting forward Scott Hogan bagged a hat-trick.
But the powerful stopper revitalised his career in the months after under Carlos Corberan. He netted the winner in just Corberan’s second win – the first on the road – at QPR and from then became a key regular in the side.
Albion sporting director Andrew Nestor said: “I’d like to thank Kyle for his efforts during his years at The Hawthorns.
“He helped lead the team both on and off the pitch – often by putting his body on the line in the heart of our defence.
“Making more than 200 appearances for one club is rare nowadays and we are grateful to Barts for his seven years’ service to Albion.
“I’m sure all associated with the football club will join me in wishing Kyle and his family all the very best for the future.”
Bartley’s retirement leaves Mason’s central defensive options as Torbjorn Heggem, new recruits Nat Phillips and George Campbell and Caleb Taylor.
Heggem’s future is in the air after negotiations with Bologna over a £10million move to Italy. They were on hold as of this week but could be revisited later in the window. Albion are in the market for defensive reinforcement this month.