Born in Ascot, but raised in Australia from the age of 16, Ball arrived in Llanelli in 2012 from Super Rugby side Western Force.
In a nine-year stint, Ball was part of the Scarlets squad that won the Pro12 league title in 2017 and reached the European Champions Cup semi-final the following year.
Ball left Scarlets in 2021 to return to Australia and had a playing spell in Japan before returning to Wales.
“The Scarlets supporters here are an awesome bunch, their passion for the team is incredible and they have been amazing to me and my family,” said Ball.
“There have been some incredible highs, the lead-up to winning the championship in 2017 and Europe the following year.
“That was a special time with a special group of players. I will always remember the friendships, the people who have made my time here so memorable.”
Ball, who qualified for Wales through his father who is from Colwyn Bay, made his Wales debut in 2014.
He was part of the Grand Slam-winning side in 2019 and a World Cup semi-finalist that same year.
The no-nonsense lock formed an international partnership with Alun Wyn Jones, although the pair were infamously involved in a training ground scuffle during the 2021 Six Nations campaign.
Ball played his final Test in the victory against Italy in Rome in March 2021 with Wales going onto to win the Six Nations title that season.
He is the latest Grand Slam-winning Wales international to announce their retirements following former Scarlets trio Liam Williams, George North and Leigh Halfpenny.
