In August 2008, Wilnis signed for Grays Athletic on a one-year contract. He retired at the end of the 2008–09 season. Wilnis played his last game for Ipswich Town in his Testimonial game with Colchester United in 2009. A stunning own goal from Colchester defender Magnus Okuonghae and a strike from Jordan Rhodes gave the Blues a 2–0 victory. Fabian Wilnis made his final appearance in a Town shirt with 12 minutes left, his every touch applauded by the Blues supporters. After the final whistle Fabian Wilnis thanked and said goodbye to Town fans for the final time at the end of his distinguished 11 years in English football, 10 of them with the Blues.