In individual competitions at FIS Nordic World Ski Championships 2013 took 31st place on the normal hill and 20th on the large hill. On 2 March 2013 he won there a bronze medal in team competition with teammates: Kamil Stoch, Maciej Kot, Piotr Żyła. Kubacki jumped 126 m and 128 m. The primary outcome of the competition his team took fourth place, but after re-counting the scores because of Thomas Morgenstern, who noticed a mistake in points and at the request of the Germans, they finished in third place.
2014/2015
Kubacki took part in the World Championships 2015 in Falun, Sweden. He was in the competition on the large hill Lugnet and was qualified to second round, but he took 29th place.
2016/2017
On 3 December 2016 Polish national team including Żyła, Stoch, Kubacki and Kot won first competition in team for Poland in history. In Zakopane Polish team, including Stoch, Kubacki, Kot, Żyła achieved second place in team competition. On 28 January 2017 Poland won their second team competition in history in Willingen. On 4 March 2017 Polish national team, including Żyła, Kubacki, Kot and Stoch, achieved first in history title of 2017 World Champions in team event. They beat Norway and Austria at Salpausselkä K116 in Lahti, Finland.
2017/2018
The summer season was very successful for him. He won 5 of 9 competitions: in Wisła, Hinterzarten, Courchevel, Hinzenbach and Klingenthal. He won all the competitions in which he took off, because he missed four competition in Japanese Hakuba and Russian Chaykovsky. He repeated the feat of Takanobu Okabe from 1994. On 3 October 2017 he won overall classification of the 2017 FIS Ski Jumping Grand Prix with 500 points. He maintained the winning streak of Poles in this tournament, repeating the success of Maciej Kot from last year. In addition, Poland triumphed in Nations Cup classification. Kubacki achieved a good results since the very start of the winter season, after the winning overall classification of the Summer Grand Prix. On 30 December 2017 Kubacki reached the lowest level of podium in Oberstdorf, behind winner Kamil Stoch. He waited 143 competitions for his first individual podium. He had a chance to reach overall podium of 2017-18 Four Hills Tournament, but he lost his chance in last jump in Bischofshofen and in the final summary he took 6th place, which was his best result in Four Hills tournament in career. On 21 January 2018 Polish national team in squad: Stoch, Hula, Kubacki, and Żyła, won the first ever medal, a bronze, for Poland in ski flying in team competition. On the same day, coach Horngacher officially appointed him to 2018 Winter Olympics. Once again, Kubacki took the third place in the competition, this time in Willingen. On 19 February 2018 Kubacki and his teammates Maciej Kot, Stefan Hula and Kamil Stoch achieved first medal in Olympic team competition for Poland. They claimed a bronze behind Norway and Germany.
