His best result came in the 2011 PDC Youth Tour Event at Nuland, Netherlands on 18 June 2011 as he beat fellow countryman Michael van Gerwen 4–0 in the semi-finals before losing 4–2 to Joe Cullen.

[1] In 2012, Vos earned a place in the Austrian Darts Open in Vienna by defeating Riccardo Pigliapoco and Toon Greebe in the European qualifier.

[10] Vos qualified for the 2013 World Championship by finishing sixth on the European Order of Merit,[11] taking the third of four places that were awarded to the highest non-qualified players.

[12] In his first appearance at the World Championship he faced reigning two-time champion Adrian Lewis in the first round and made a perfect start to the match as he took the first set to nil.

[16] He reached the main draw of two European Tour events during the year, losing 6–2 to Phil Taylor in the opening round of the Gibraltar Darts Trophy, and beating Richie Burnett 6–4 in the Dutch Darts Masters (having held off a fightback from the Welshman as Vos had led 5–1), before Michael Mansell defeated him 6–2 in the second round.

[22] Vos dropped outside of the top 64 in the world rankings in January 2015 as he was number 87 and therefore entered Q School in an attempt to win his spot back.