The Arizona Republic reported Monday that Markieff Morris will receive a four-year deal worth $32 million while Marcus Morris will get a four-year deal worth $20 million.
ESPN.com first reported Sunday night that the two brothers would split a long-term total of $52 million.
"We are particularly pleased to have reached extension agreements with Marcus and Markieff before the start of training camp," Suns president of basketball operations Lon Babby said in a release. "There is an extraordinary bond between these twin brothers; they make each other better players and better men. We take pride in their growth and look forward to their bright futures."
Added general manager Ryan McDonough: "They have made great strides over the past year and we feel like they will continue to grow and improve. They are just entering their primes and we think they will play the best basketball of their careers over the course of the next five years."
Babby told reporters that the brothers decided how to divvy up the money.
"I did something I've never done before," Babby said. "Once we agreed on the amount of money ($52 million over four years), I gave them the first crack at how to divide it up."
The Suns also recently completed the signing of point guard Eric Bledsoe. Phoenix secured Bledsoe for the long term last week with a five-year deal worth $70 million after a summer of acrimonious negotiations.
The Suns also signed Zoran Dragic -- brother of star guard Goran Dragic -- to a two-year deal worth just over $4 million. Fresh off a season that earned him All-NBA third-team honors, Goran Dragic is expected opt out of the final year of his contract after the 2014-15 campaign to become an unrestricted free agent on July 1.