The teenager also confirmed the wedding will be taking place at the Australia Zoo, which is owned by their mom, Terri Irwin. "You're always with me", she wrote.
"We were in the gardens of Australia Zoo and it was beyond ideal".
"Chandler and Robert (Bindi's brother) worked together to capture the moment I said "YES", the Australia Zoo heiress captioned a series of proposal photos. Mum helped me get ready, Robert walked me down the aisle, Chandler became my husband and together we lit a candle in Dad's memory.
Chandler posted the same photo, writing, "We're finally married!" "I married my best friend". Thankfully, since we all live at Australia Zoo as a family, we could be there for each other.
Powell, 23, proposed to Irwin on her 21st birthday in July past year, after the pair met at Australia Zoo in 2013.
Bindi's 3.3 million-strong Instagram following has kept up with Bindi and Chandler's love story with the wildlife crusader sharing intimate moments, including when she said "yes" to her wedding dress in September a year ago.
Instead, the bride and groom exchanged vows in front of close family members during a private ceremony.
Chandler is a wakeboarder from Seffner, Florida. "I'm like, 'Wow she is wonderful'".
Irwin's mother, Terri Irwin, and her younger brother, Robert, shared their joy and approval over the exciting engagement news a year ago with Terri writing on social media that it was the "best day ever".
The pair "hit it off right away", he said, adding, "We haven't looked back since".
On Tuesday, the 21-year-old sweetly shared a photo on Instagram of her father Steve, who tragically lost his life in 2006 after being stung by a stingray.
"Thank you for being my guiding light", she wrote.
"I know you'd be beaming with pride when the time comes that he walks me down the aisle", Bindi continued. I know that Dad was with us, and we are all so delighted for your future as husband and wife.
Irwin often pays tribute to the special connection she shared with her father.
"He loves wildlife and conservation and he has this strength - which is necessary when you're jumping on crocs!" she said.