"16 years and it feels like we're just getting started... I love you Chip Carter Gaines," Joanna wrote in the caption, alongside a photo of the couple outside their home with smiles from ear to ear.
The post earned more than 1 million likes in just the first six hours after it was posted. Even Counting On star Anna Duggar, the wife of Josh Duggar, wrote "Happy Anniversary!"
"Big congrats to you both," Little People, Big World star Amy Roloff added.
"You guys are so cute together. Wishing you many years of love, health and happiness," one fan wrote.
"Happy anniversary!!! My husband and I are celebrating 16 years today tooo!!!" another fan wrote.
Gaines and Chip have been married since 2003 and have five children, Drake, 14, Ella, 13, Duke, 10, Emmie, 8, and Crew, 9 months.
The couple starred on HGTV's Fixer Upper from 2013 to 2018, and have focused on their Magnolia business empire. The two are also working on launching their own network, which will replace Discovery's DIY network. It will launch in 2020 and is slated to include shows about lifestyle, wellness and design. New shows will go behind just renovating houses.
"The difference moving forward is Jo and I are going to be able to tell more of our life stories," Chip explained to USA Today earlier this month. "And so, as opposed to it being a very narrow vein in our universe, which is obviously construction and design and the things we do for a living, for us we feel like there’s a more holistic story to be told here, and that’s what we’re going to focus on."
"We loved this idea of connecting with people in a different way... telling other people's stories, curating content," Gaines explained. "It felt to us a lot like what we do love with the magazine, but on a different playing field."
Gaines said their children are aware of their new venture, but are not pushing them to appear on the network. They want to see their children find their own interests.0comments
"They're just all getting to this beautiful age where they’re starting to figure out what they love, what they’re passionate about," she told USA Today. "When they were younger, when we were doing Fixer, it was natural for them to be on my hip. As they got older, we just never wanted to force the scene, we always told our kids, 'If you want to be part of this, we'll put a mic on you.' If the kids want to do it, we would gladly welcome it, but we'll leave it up to them."
Photo credit: Instagram/Joanna Gaines