The game was a rematch of the Olympic gold medal contest in Sochi, which Jones won 6-3.
Down 4-3 in the seventh end on Saturday, Jones scored a single to tie the game before Sigfridsson put up the decisive point.
Sigfridsson will play Edmonton's Val Sweeting in Sunday's final after Sweeting edged Ottawa's Rachel Homan 4-3 in nine ends in the other women's semi.
Homan trailed 3-2 before tying the game with a single in the eighth end to send it to extras.
Earlier in the day, Jones scored two points in the final end for a 6-5 victory over Sherry Middaugh of Coldwater, Ont., while Homan put up three points in the seventh end to beat Silvana Tirinzoni of Switzerland 8-3. Sigfridsson had two points in the fifth and added single steals in the sixth and seventh ends to double up Binia Feltscher of Switzerland 8-4, and Sweeting downed Switzerland's Alina Paetz 5-2.
On the men's side, St. John's Brad Gushue will meet 2010 event winner Mike McEwen of Winnipeg in the championship game.
Gushue earned a point in the extra end to beat Toronto's John Epping 6-5.
The two rinks would exchange doubles in the first two ends before Gushue scored singles in ends four through six. Epping would connect for a point in the seventh and eighth end to force extras.
In his semifinal against Sault Ste. Marie, Ont.'s Brad Jacobs, McEwen scored four in the second end and three in the fourth en route to a 7-2 victory.
Jacobs opened the scoring by getting a single in the first end before McEwen broke the game open in the second. The two rinks would call the game after five ends.
Earlier in the day, McEwen defeated Saskatoon's Steve Laycock 9-3 while Gushue booked his ticket to the semifinals with a 5-4 win over Winnipeg's Jeff Stoughton. Epping edged Switzerland's Sven Michel 5-4 and Jacobs scored two in the eighth to beat Calgary's Kevin Koe to round out quarterfinal action.