Entering the night in 12th after the first two of four runs completed yesterday, the pair laid down a 1:02.04 in run three to jump into 11th, within striking distance of a top-10 finish.
However, a difficult fourth run saw a 1:02.51 time for the duo to finish with a combined time of 4.08.64 in 16th.
The event was dominated by Germany, who took out gold and silver, with USA winning bronze. The winning pair of Laura Nolte and Deborah Levi finished well clear of the pack, more than 1.5 seconds ahead of bronze and 4.68 seconds ahead of the Australian duo.
The Australian pair's finish is just short of Astrid Loch-Wilkinson and Kylie Reed's 14th at Torino 2006, Australia's best ever result in the discipline. The full body of Bree and Kiara's four runs show the pair finished less than half a second outside the top 10.
While disappointed at their final run, the pair were proud of their campaign to take on the giants of the bobsleigh world.
"I don't have words for how I'm feeling yet, I'm still comprehending what has happened," Bree said. "It's been a huge campaign but I'm so grateful for our team, we've worked so hard.
"I really wanted to fix up a few mistakes I had been making all week and I think that last run I wanted it too bad.
"We couldn't have made it here or achieved what we have on our own, I'm so grateful for the team. We're all pretty much freshies, on our first Olympics, out here having a crack and making it happen."
Bree was excited to head back to Australia after more than two years away from friends and family chasing her bobsleigh dream in Europe and North America.
"We're going to head home and come down from this whole experience. I'm so excited to see my family, it's been two and a half years, I can't wait to give you all a hug."
Brakewoman Kiara, who only paired with Bree for the first-time last year, paid tribute to the work the team had put in to make their debut Olympics.
"I'm really proud of how we've done this whole campaign," the West Australian said. "This is our first Olympics and just our fourth race together.
"The thing I really like about Bree is she's willing to risk it, she's willing to chuck herself out there to find the fast lines. It might not have worked out in that final run, but we gave every single part of ourselves to this experience and this journey, you can't be more proud or happy with that.
"I'm honoured to slide with Bree and be part of this team. It's been a really long season for us, we've been away from Australia for so long."
While they would have liked to have been better in their final run, they know that doesn't define the next four years as they continue to grow and challenge the traditional sliding heavyweights.
"I love the sport and everything about it," Kiara said.
"If we can get some support behind us, it's a big campaign, I'm going to try my best to really pump it up for the future."
And after achieving Australia's best ever Olympic bobsleigh result with fifth in the monobob, and achieving 16th after just their first season together, the future is looking very bright for Australian women's bobsleigh.