Biggar admitted wearing the prestigious 10 shirt for Wales “hasn’t always been plain sailing and easy”, but it helped to make him a stronger person and player.
He also reflected on a difficult past year at Toulon.
“I also know that the last 12 months haven’t quite gone as I’d hoped with Toulon, it’s been tough and setbacks teach you a lot more about yourself and over the last 12 months I’ve learned a huge amount,” he said.
“There’s no real perfect moment to walk away, but this does feel like the right one.
“I’m choosing to retire, which a lot of sportspeople don’t get to do when they’re healthy and I feel very grateful and excited about what’s coming next.
“Rugby will always be a part of me, but now it’s time to give a little bit of time back to my family in this beautiful part of the world and see what challenges come next.”
Biggar finished by thanking the game of rugby itself, the people, the memories and lessons.
“I can honestly say I gave it everything I had and now it’s time for something new,” he said.
“Thank you, diolch, merci.”