The NBA's 30 teams were notified shortly after 5 p.m. ET on Sunday that the Suns won the blind bidding for Scola, which requires interested teams under the salary cap to bid no less than $3 million for this season and $10-plus million for the next three seasons.
It was not immediately known how many teams placed bids on Scola beyond the Suns and the Dallas Mavericks.
"We are excited to have won the bid for Luis Scola and to add a player of his caliber to our roster," Lon Babby, the Suns' president of basketball operations, said in a release. "We greatly value the production he will bring and the leadership he will provide to our younger players."
The Suns also used their own amnesty provision Sunday on forward Josh Childress, sources told ESPN.com's Brian Windhorst. The move allows Phoenix to waive the final three years and $21 million on Childress' contract from its salary cap.
The 6-foot-9, 245-pound Scola averaged 15.5 points and 6.4 rebounds last season for the Rockets, who used their amnesty provision to waive the remaining three years and $21 million on his contract.
Scola is set to join a frontcourt that features newly acquired forward Michael Beasley, who agreed to terms with Phoenix on an $18 million contract earlier this month, according to sources. The Suns also recently landed Goran Dragic to replace Nash, agreeing with the free agent point guard on a $34 million deal, according to sources.
ESPN.com's Brian Windhorst and The Associated Press contributed to this report.