The Sharks booked a place in the Currie Cup final against Western Province at Newlands when they beat the Cheetahs 33-22 at Kings Park in Durban.
Patrick Lambie scored 23 points including one of three tries for his side, adding to scores by Jacques Botes and Heimar Williams.
The flyhalf also kicked four penalties and three conversions as the coastal side ensured a repeat of last year's final, although Cape Town will play host in 2013.
Their opponents from Bloemfontein gave them a good go with three tries of their own through Lappies Labuschagne, Johann Sadie and Schalk van der Merwe, but were punished by the clinical hosts.
The Free Staters began with a bang by crossing the try-line inside three minutes after the start when SP Marais clearance kick went horribly wrong and allowed Philip van der Walt to pop a pass up to Labuschagne to score.
The Sharks hit back in the seventh minute when visiting captain Adriaan Strauss conceded a penalty at the scrum, with Lambie sending over the three points.
Smit had a chance to restore the seven-point lead before the first quarter mark when Wiehahn Herbst conceded a penalty for illegal binding at the scrum, but the Cheetahs winger sent his effort wide.
Lambie returned the favour, though, and fluffed a straightforward chance when Boom Prinsloo was off-side not long after.
The Sharks pivot did not make the same mistake twice, and after Prinsloo failed to release in the tackle, he slotted over the penalty to cut the gap to one.
Two minutes before the interval, Lambie put the Sharks ahead when he collected a quick ball from Charl McLeod and slipped inside through two tacklers on his way to running in under the post.
With the siren looming, Strauss was penalised for another error, this time for not rolling away right in front of his goal-line, allowing Lambie to extend the lead to nine by the break.
Johan Goosen continued his comeback from a long injury layoff when he was introduced after the interval and he scored the opening points of the second half with a penalty conversion.
Botes, however, extended the lead for the hosts when he broke a few tackles in the 51st minute to score on the right of the posts after Marcell Coetzee carried strongly and provided the crucial pass for his fellow loose forward.
The Cheetahs were reduced to 14 men before the hour when scrumhalf Piet van Zyl was sent to the sin bin for a deliberate trip on Marais.
Lambie then extended the lead in the 63rd minute after Van der Merwe was called for collapsing the scrum, before the numbers levelled up again when Bismarck du Plessis was yellow carded for stamping.
From the resulting scrum, the ball was quickly spun left with Robert Ebersohn sending Sadie away to give the Cheetahs hope.
That optimism was quickly killed off when Williams was one of a number of players free on the left to dart over to wrap up the win.
Even though Van der Merwe added a late score, it turned out to be only a consolation as the Durbanites booked their ticket to Newlands next week.
Final Score Sharks 33 (16) Free State Cheetahs 22 (7)
Tries: Patrick Lambie, Jacques Botes, Heimar Williams
Conversions: Lambie (3)
Penalties: Lambie (4).
Free State Cheetahs
Tries: Lappies Labuschagne, Johann Sadie, Schalk van der Merwe
Conversions: Riaan Smit, Johan Goosen
Referee: Marius van der Westhuizen
Assistant Referees: Rasta Rashivhenge, Cobus Wessels
TMO: Deon van Blommestein
The Sharks: SP Marais; Odwa Ndungane, Louis Ludik, Francois Steyn, Lwazi Mvovo; Pat Lambie, Charl McLeod; Keegan Daniel (capt), Jean Deysel, Marcell Coetzee; Pieter-Steph du Toit, Peet Marais; Wiehahn Herbst, Bismarck du Plessis, Tendai Mtawarira.
Replacements: Kyle Cooper, Danie Mienie, Stephan Lewies, Jacques Botes, Cobus Reinach, Fred Zeilinga, Heimar Williams.
Free State Cheetahs: Hennie Daniller; Riaan Smit, Johann Sadie, Robert Ebersohn, Raymond Rhule; Elgar Watts, Sarel Pretorius; Philip van der Walt, Pieter Labuschagne, Boom Prinsloo; Lood de Jager, Francois Uys; Trevor Nyakane, Adriaan Strauss (capt), Coenie Oosthuizen.
Replacements: Hercu Liebenberg, Rossouw de Klerk, Teboho Mohoje, Freddy Ngoza, Piet van Zyl, Johan Goosen, Ryno Benjamin.