Three Nations Senior Lacrosse League
TNSLL | |
| Sport | Box lacrosse |
|---|---|
| Founded | 2009 |
| No. of teams | 4 |
| Confederation | First Nations Lacrosse Association |
| Most recent champion | Snake Island Muskies (2025) |
| Most titles | Snake Island Muskies (8) |
| Official website | gamesheetstats |
The Three Nations Senior Lacrosse League (TNSLL) is a Senior B box lacrosse league based out of Ontario, Quebec and New York, sanctioned by the First Nations Lacrosse Association (FNLA). The league champion earns a spot in the Presidents Cup, the national championship of Senior B lacrosse in Canada.