The Swans 16.12 (108) defeated the Tigers 6.8 (44) to finish the home-and-away season with 13 wins and record their third win in succession.
It will be Sydney's first back-to-back finals series since 1998-99 and it will be its first finals match against West Coast.
Sydney coach Paul Roos said in his post-match media conference that he was pleased with his side's performance as it enters the finals, but he also put the 10-goal-plus win in perspective.
"It's good to have a really good win in round 22 and it's good to have some of your better players in good form, but we all know that the season's finished and you go onto finals and in a certain sense, everyone's equal, other than the fact that top four get the double chance, so we're really looking forward to it," Roos said.
But Roos conceded he wouldn't take too much from the thrashing against Richmond, as he said his focus would quickly be on next week's opponent, the Eagles.
"It's now onto whoever we're going to play next week. You're really not going to look too much at that game, probably you'll watch it, but I don't think you'll take too much out of it and basically concentrate on your opposition for next week," Roos said.
Sydney's Nick Davis was one of his side's best against Richmond with five goals after starting the match on interchange.
His return in the past month, after an injury-interrupted season, which has included hip, thigh and ankle problems, is major plus.
Forwards Michael O'Loughlin and Ryan O'Keefe chipped in with three majors each and were also important contributors while Barry Hall finished with two majors to take his season tally to 70 goals.
Key ball-winners Jude Bolton, Ben Mathews, Brett Kirk, Paul Williams and Stuart Maxfield were also significant as they combined to crack the ton with over 100 touches.
'Leaping' Leo Barry showed why he is a genuine 2004 All-Australian contender in the back-half, having achieved 10 kicks, 10 marks and 10 handballs. And if his coach has his way, he will be named in the elite 22.
"If I was picking it, he'd be in, but I'm not picking it. He's been outstanding all year - no doubt," Roos said.
"He's really elevated another (level this year) and I thought last year he was a little bit stiff to miss out, but it's very hard to get in and it's elite team and there are some terrific players that miss out. Certainly, he's knocking down the door this year."
Although Richmond led by eight points at quarter-time, Sydney piled on three goals to zip in the second term to lead by 12 points at the main break.
From Davis' first at the 27-minute mark of the first term, through to Hall's goal at the 23-minute mark of the third term, the Swans made it eight unanswered goals, before the Tigers posted their fifth for the day.
This set up Sydney's victory, as it led by 32 points at the final change, before it became party time for the Swans in the final term, when they added a further six goals to one to runaway with the easiest of victories.
Richmond: 4.4 4.7 5.8 6.8 (44)
Sydney: 3.2 6.7 10.10 16.12 (108)
Goals: Richmond: Richardson 3, Coughlan, Krakouer, Gaspar 1
Sydney: Davis 5, O'Loughlin, O'Keefe 3, Hall 2, Williams, Kirk, J Bolton 1
Best: Richmond: Richardson, Gaspar, Bowden
Sydney: Mathews, O'Loughlin, O'Keefe, Williams, Kirk, Davis, Nicks
Injuries: None
Reports: None
Umpires: Dore, Nicholls, Wenn
Crowd: 29,777 at the MCG
