The "Being Mary Jane" actress and Miami Heat basketball champ shared the news in a handful of Instagram photos over the weekend.
"Sooooo this happened... #Yessss," the 41-year-old actress wrote, captioning a photo of an enormous cushion-cut sparkler settled snugly on her ring finger.
Her fiance echoed the sentiment, sharing the same photo with the caption: She said YES!!! @gabunion"
The couple, who have been dating since 2009, got engaged in Miami on Saturday, according to Us Weekly.
Wade, 31, also shared an adorable photo of the moment after the proposal, with the basketball star still down on one knee and Union burying her face as she hugs him close.
Union then took to Twitter to share her glee.
"Maaaaaannn... I'm floatin! Thank you SO much for all the love, well wishes & support!" she wrote, adding, "And yes my hands were ashy ... And yes my nails arent done... I was truly caught off guard but happy nonetheless :) lmao #ashyknucklesbringgoodluck"
But the best status came when Union gave a shoutout to her friends, adding, "It aint real until u go to Red Lobster to celebrate!"
The couple reportedly this year sent out Christmas cards together from the "Wade-Union Family," People magazine reported.
But let's talk about Union's new piece of bling! The ring features an 8.5-carat diamond solitaire by Jason of Beverly Hills, E! News reported. It's value? Nearly $1 million.
"Dwayne Wade was 100% involved in the process," Jason Arasheben, chief executive of Jason of Beverly Hills, told E!.
"I made three personal visits to Miami to present different options until they found the perfect one. Wade picked out the stone and they made the ring custom."
"[Dwayne] was very particular about finding the right stone for Gabrielle," Arasheban said. "He was hands on in the process he and I worked together to make sure they got the perfect ring for Gabrielle."
This will be the second union for both stars.
Union married football player Chris Howard in 2001, but they separated in 2005 and divorced in 2006.
Wade was previously married to his high school girlfriend Siohvaughn from 2002 to 2007. Their long-running divorce didn't become until 2010.
Wade has two sons from the union, Zaire Blessing Dwyane Wade and Zion Malachi Airamis Wade.
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