"Home Is Where The Heart Is ... My Home, My City, My House," the free-agent guard tweeted along with the hashtag #HeatLifer.
The deal for Wade to stay in Miami, where he's spent his entire 11-year career and won three NBA titles, has been finalized but not signed by Wade, according to ESPN.com.
After James announced last week that he was leaving to play for the Cleveland Cavaliers again, Bosh re-signed with the Heat on a reported five-year, $118 million deal.
So it looks like two of the Heat's Big Three will be back after four straight trips to the NBA Finals, including back-to-back championships in 2012-13.
Wade led Miami to its first title in 2006 but his scoring output has declined in each of the past five seasons since he led the NBA in 2009.
He averaged 19.0 points in 54 games this past season as he battled knee and hamstring ailments, his lowest output since his rookie season out of Marquette in 2003-04.