Six Nations may refer to:
Organizations
Political organizations
- Iroquois, an alliance of Indigenous nations in North America
- Celtic League, alliance of six Celtic "nations"
Schools
- Six Nations Polytechnic, third-level college in the reserve
Places
- Six Nations of the Grand River, First Nations reserve in Canada
Sports
- Six Nations Championship, an annual European men's rugby union competition
- Six Nations Under 20s Championship, under-20 men's equivalent
- Women's Six Nations Championship, women's equivalent
- Six Nations Tournament (ice hockey), a 1994–1996 European men's ice hockey competition
- ICC Six Nations Challenge, a 2000–2004 men's cricket tournament
See also
- Six-party talks, worldwide discussions aimed at resolving security concerns related to North Korea’s nuclear weapons program
- Six Nations land cessions, by Iroquois and Lenape 17th and 18th centuries to British North America
- Nations Cup (netball), an annual tournament held in Singapore