It marks the end of her 22-year contribution to local government in Christchurch and four years representing part of the Bay Harbour area.
Buck served as a Christchurch city councillor, representing the Waimairi Ward, from 1998 to 2013.
She then served a term on the Fendalton-Waimairi Community Board before being elected to the Linwood-Central-Heathcote Community Board in 2016 where she served as chairwoman.
Buck was re-elected to the Linwood-Central-Heathcote Community Board in October 2019.
She resigned from her role as chairwoman in April for health reasons, and the position was taken over by board member Alexandra Davids.
"I’ve loved serving the community and making changes in the city.
"It’s been a huge privilege to meet so many wonderful people through this role and it’s been an incredible insight into the wonderful community that is Christchurch.
"I’ve loved seeing new ideas and new projects come to fruition and seeing people enjoy them," Buck said.
Meanwhile, Banks Peninsula Community Board chairwoman Tori Peden, who was diagnosed with bowel cancer in April, will step down from her role for the next six weeks.
She is set to undergo surgery on Tuesday to remove the tumour.
“It’s kind of like dermatitis. [Treatment] has flared up the skin condition but they need the skin to be healed so they can do the surgery.
“They stopped the treatment and they’ve decided to go with the surgery.”
Banks Peninsula Community Board deputy chairman Tyrone Fields will step into the role of chairman from Tuesday until Peden has recovered.
“I’ve had amazing support come through the community from many different people and it has been lovely. It’s nice to know people care.”