Because of the knee injury, Boëtius missed the beginning of the 2013–14 season. He made his season debut on 15 September 2013 coming off the bench in the 62nd minute against NEC Nijmegen. Just five minutes after entering the pitch Boëtius scored a goal giving his team a 2–1 lead. During the season Boëtius scored 10 goals in 29 appearances. He finished 3rd among the league's assists leaders with a total of 9 assists. Feyenoord ended the season on the second place only behind Ajax, earning a spot in the UEFA Champions League third qualifying round.
On 6 March 2013, Boëtius was called up for the preliminary squad of the Dutch national team for the first time, aged only 18. He made his debut for the Netherlands national team on 5 March 2014 in an exhibition match against France at Stade de France in Saint-Denis. He started the match as a left winger but was substituted in the 72nd minute as the Netherlands were defeated 0–2.