Holding a narrow overnight lead, the SA team defeated Western Australia 3.5-1.5 this morning to seal victory.
South Australia's Jack Williams (Grange) was the only player to remain undefeated for the championship.
Queensland's 3-2 win over Victoria was enough to elevate them into second place, finishing half a contest ahead of the Victorians in third.
New South Wales moved up to fourth place, leapfrogging Western Australia who finished fifth.
The Northern Territory, ACT and Tasmania finished in sixth, seventh and eighth respectively.
South Australian Team:
Matthew Lisk (Grange) (Captain)
Anthony Murdaca (Grange)
Lachlan Booth (Glenelg)
Jack Williams (Grange)
Kieran Barratt (Thaxted Park)
Jordan Bishop (Kooyonga)
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