With the F1 drivers finally able to get some dry running under their belts at Silverstone, Sebastian Vettel emerged as the one to beat.
While off-throttle blown diffuser row rumbled on in the background, the reigning World Champ crossed the line with a 1:31.404, making his mark ahead of qualifying.
However, the German was not in a class of his own as Ferrari's Fernando Alonso was just 0.063s off the pace.
Mark Webber, the defending British GP Champ, was third ahead of Felipe Massa and Pastor Maldonado.
Jenson Button was the best placed Brit in sixth place, 1.555s adrift of Vettel.
Report: A sold-out crowd surrounded the track as final practice got underway on Saturday morning with Tonio Liuzzi kicking off proceedings by running wide and cutting the grass. Nico Rosberg, though, wasn't to be outdone and had a brief fire at the back of his Merc GP W02 - and all this before even one lap time had been set.
Jaime Alguersuari crossed the line with a 1:38.936 with Jarno Trulli and Jerome D'Ambrosio slotting in behind him. Michael Schumacher took over at the top with a 1:36.228. Kamui Kobayashi went second and Mark Webber third. Both, though, soon overhauled the Mercedes GP driver, Webber going fastest with a 1:34.699.
20 minutes into the session, the rain began to fall lightly over the circuit.
Felipe Massa moved up to fourth place with Jenson Button fifth and Nico Rosberg P6. Moments later the drivers poured into the pits and concerns increased over the lack of dry running. Problems for Webber, whose RB7 was in pieces as his team worked furiously to resolve what looks to be an engine issue.
Back on the track with the drizzle having eased up, the two Ferraris put in the laps evaluating the harder tyres while Alguersuari hit the front before losing out to Rosberg with a 1:33.044. Rosberg's team-mate Schumacher was stuck in the pits with what looked to be an exhaust problem. His W02's floor had even been removed. Massa improved to third before he was dropped by Alonso, both still on the harder tyres.
Alonso moved up to second as Webber climbed out of his car. Sebastian Vettel took fourth place ahead of Paul di Resta before the Scot overhauled the reigning World Champ. Alonso took another step up to first but was topped by Pastor Maldonado only to return with a 1:31.464. But again he was dropped, this time by Vettel, who posted a 1:31.401, 0.063s up on Alonso's best.
Practice Three ended with Vettel in the P1 slot, followed by Alonso, Webber and Massa.
Times
01. Sebastian Vettel Red Bull-Renault 1m31.401s 17 laps
02. Fernando Alonso Ferrari 1m31.464s + 0.063s 20 laps
03. Mark Webber Red Bull-Renault 1m31.829s + 0.428s 12 laps
04. Felipe Massa Ferrari 1m32.169s + 0.768s 20 laps
05. Pastor Maldonado Williams-Cosworth 1m32.496s + 1.095s 20 laps
06. Jenson Button McLaren-Mercedes 1m32.956s + 1.555s 18 laps
07. Kamui Kobayashi Sauber-Ferrari 1m33.014s + 1.613s 20 laps
08. Nico Rosberg Mercedes 1m33.044s + 1.643s 23 laps
09. Sergio Perez Sauber-Ferrari 1m33.264s + 1.863s 21 laps
10. Paul di Resta Force India-Mercedes 1m33.423s + 2.022s 22 laps
11. Michael Schumacher Mercedes 1m33.551s + 2.150s 11 laps
12. Adrian Sutil Force India-Mercedes 1m33.660s + 2.259s 22 laps
13. Lewis Hamilton McLaren-Mercedes 1m33.842s + 2.441s 16 laps
14. Rubens Barrichello Williams-Cosworth 1m33.905s + 2.504s 21 laps
15. Vitaly Petrov Renault 1m34.042s + 2.641s 22 laps
16. Jaime Alguersuari Toro Rosso-Ferrari 1m34.329s + 2.928s 20 laps
17. Sebastien Buemi Toro Rosso-Ferrari 1m34.799s + 3.398s 20 laps
18. Nick Heidfeld Renault 1m34.822s + 3.421s 21 laps
19. Heikki Kovalainen Lotus-Renault 1m35.225s + 3.824s 21 laps
20. Jarno Trulli Lotus-Renault 1m36.905s + 5.504s 21 laps
21. Timo Glock Virgin-Cosworth 1m37.614s + 6.213s 18 laps
22. Jerome D'Ambrosio Virgin-Cosworth 1m38.068s + 6.667s 20 laps
23. Daniel Ricciardo HRT-Cosworth 1m38.289s + 6.888s 19 laps
24. Tonio Liuzzi HRT-Cosworth 1m38.568s + 7.167s 17 laps
