The 31-year-old, who started his career as an inaugural GWS player, was a key member of the Magpies' 2023 flag triumph.
But he faces a fight to break back into the Pies' line-up for the upcoming finals series, after being dropped for last week's loss to Adelaide.
Hoskin-Elliott, who has played 242 AFL games, on Wednesday told teammates and staff of his decision to hang up his boots.
"I'm proud and honoured to call myself a Collingwood player and I have loved my time in the black and white," Hoskin-Elliott said.
"I leave with incredible memories, lifelong friendships and I can't wait to see what the rest of this season holds for us.
"Running out in the black and white, alongside my teammates, with the Magpie Army behind us, is so special.
"The feeling of hearing 'Collingwood' echo around the MCG, knowing we have such incredible fans, is what makes me so proud to play for Collingwood."
Hoskin-Elliott started his career with GWS in 2012 and spent five seasons with the expansion club before switching to Collingwood.
Regarded as a team player, the versatile goal-kicker became an important part of the Magpies' teams under coaches Nathan Buckley and Craig McRae.
He kicked a career-best 42 goals in 2018, when the Pies lost the grand final, and played 23 of a possible 26 games in the run to the 2023 premiership.
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