Following confirmation of his Scarlets departure, Davies stated he was seeking one further opportunity in club rugby.
Davies played his junior club rugby for St Clears and Whitland before coming through the Scarlets academy.
The centre captained Wales on four occasions and played six Tests on two tours with the British and Irish Lions, in 2013 in Australia and New Zealand in 2017 – earning the player of the series award against the All Blacks.
Davies – nicknamed Foxy – won two Grand Slams and a further two Six Nations Championship titles in addition to playing in two World Cups with Wales.
The centre – who also had two years with French side Clermont Auvergne – helped Scarlets win the Pro12 title in the 2016-17 season.
“There are too many people to thank; the dedicated and loyal fans, quality team mates, supportive coaches, staff, friends, and most of all, my family, all who have believed in me,” Davies added on Instagram.
“I am so grateful for the support, especially when faced with the challenges and setbacks of injuries. It’s been an incredible ride, with two Lions tours, two Grand Slams, and the Pro 12 title to name a few.
“I have been lucky enough to play the game professionally for 18 years, dedicating everything I have to being the best rugby player I could be.
“I now look forward to what the next 18 will bring, as a father, a husband, and in my next professional chapter. Diolch, Foxy.”