In British rugby league, winning the Treble currently refers to winning the Super League Grand Final, League Leaders' Shield, and Challenge Cup in the same season. Up until 1973 this was achieved by winning the Championship Final, finishing top of the league during the regular season, and winning the Challenge Cup.
Between 1973 and 1996, following the abolition of the Championship Final, the league leaders were declared season champions. In this era, the Premiership was the third trophy required for the treble.
Only six teams have completed the treble, and it has only been achieved three times during the Super League era. Wigan Warriors are the most successful team, winning the treble on 3 occasions.
Men's Treble
Bradford Bulls
2003
Bradford Bulls became the first team of the Super League era to win the treble in 2003. They beat Leeds Rhinos 22-20 in the 2003 Challenge Cup Final, won the League Leaders' Shield at the end of the season (the first time the current trophy was awarded) and completed the treble by beating Wigan Warriors 25-12 in the 2003 Super League Grand Final.
Huddersfield Giants
1912-13
Huddersfield Giants were the first team to complete the treble in the 1912-1913 season, beating Warrington Wolves 9-5 in the Challenge Cup final. They then went on to finish top of the league and win the Championship Final 29-2 beating Wigan.
1914-15
Huddersfield won their second treble before going on to win All Four Cups in 1914-15, beating St. Helens 37-3 in the Challenge Cup final and then beating Leeds 35-2 in the Championship Final a few weeks after they finished top of the league.
Leeds Rhinos
2015
Leeds won their only treble in 2015. They began by whitewashing Hull Kingston Rovers 50-0 in the biggest ever win in the Challenge Cup Final to claim back to back Cup wins for only the second time. They won the League Leader's Shield after beating Huddersfield Giants in the final match of Super League XX, with winger Ryan Hall scoring in the last second to win the match. They completed the treble after beating Wigan Warriors for the first time in a major final, winning 22-20 in the 2015 Super League Grand Final.
St Helens
1965-66
St Helens won their first treble in 1966, beating Wigan 21-2 in the Challenge Cup, finishing top of the league and beating Halifax 35-12 in the Championship Final.
2006
In 2006 Saints become only the second team in the Super League era to win the treble, 40 years after winning their first. They beat Huddersfield 42-12 in the 2006 Challenge Cup final, went on to finish top of Super League and beat Hull FC, who were playing in their first Grand Final, 26-4 in the 2006 Super League Grand Final. The 2006 St Helens team became only the second rugby league team in history to win the BBC Sports Personality Team of the Year Award.
Swinton Lions
1927-28
Swinton Lions won their only treble in 1927-28 before going on to win All Four Cups. They started by beating Warrington 5-3 in the Challenge Cup and beat Featherstone Rovers 11-0 in the Championship Final after they finished top of the league.
Wigan Warriors
1991-92
Wigan Warriors won their first treble in the 1991-92 season, finishing top of the league, defeating Castleford 28-12 in the Challenge Cup final and beating St Helens 48-16 in the Premiership final.
1993-94
Wigan won their second treble in 1993-94, finishing top of the league, defeating Leeds 26-12 in the Challenge Cup final and beating Castleford 24-20 in the Premiership final.
1994-95
Wigan won the treble for a record third time in the 1994-95 season, finishing top of the league, beating Leeds 30-10 in the Challenge Cup final and beating Leeds 69-12 in the Premiership final.
Winners by club
Women's Treble
Featherstone Rovers
Fetherstone Rovers were the first women's team in British rugby league to achieve the treble in 2012 when they won the inaugural Challenge Cup, finished top of the Women's RLC Premier Division and won the Championship final.
Thatto Heath Crusaders / St Helens
Thatto Heath Crusaders achieved the treble when they won all three trophies in 2016. The team then won again under the new St Helens name in 2021.
Bradford Bulls
Bradford Bulls became the third team to complete the women's treble a year later in 2017.