Voyce, who won nine caps, was part of London Welsh's squad in the Aviva Premiership this season but his major career successes came during a six-year spell with Wasps.
The 32-year-old helped Wasps win European and domestic titles during his time with them, moving there from Bath and then leaving to join Gloucester in 2009.
He made a total of 220 Premiership appearances and is the fifth-highest try-scorer in Premiership history with 66 touchdowns.
Voyce will now take up a post with London-based foreign currency specialists Baydonhill FX.
- Sports & Recreation
- Aviva Premiership