Hitech TGR's Deagen Fairclough was fastest for the second successive session on Friday afternoon, but after topping session two by three thousandths of a second, it was even closer in the final practice, as the Brit led Patrick Heuzenroeder by 0.002s this time around.
Fairclough's session best of 1m30.009s came after a late red flag brought out by an off for Divy Nandan at turn two, and the session resumed with just over six minutes remaining on the clock, sparking a mini qualifying simulation.
With under a minute to go, Fairclough moved to the top of the pile, with Xcel's Heuzenroeder and Elite's Will Macintyre having also topped the times late on. The top-three were covered by 0.122s, but while Fairclough's lap was his best of the day, Reza Seewooruthun's lap record-beating effort in session one proved the outright best of the day.
Rodin Motorsport's Gianmarco Pradel was fourth quickest in the final session, 0.026s ahead of the second Hitech car of Nikita Johnson, with his teammate Keanu Al Azhari 0.013s further back to complete the top six, split by two tenths of a second.
Argenti with Prema's Seewooruthun was seventh fastest in the final session, 0.004s clear of the lead JHR car of Kai Daryanani, with the Indian's teammate and de facto championship leader Noah Lisle ninth.
Rodin's Alex Ninovic completed the session three top-10, which was covered by 0.657s. GB3 action resumes on Saturday with the two-part qualifying session due to commence at 10.20 local time (09.20 UK).
GB3 Championship, partnered by the BRDC, Zandvoort Free Practice Three result:
1. Deagen Fairclough, Hitech TGR, 1m30.009s
2. Patrick Heuzenroeder, Xcel Motorsport, +0.002s
3. Will Macintyre, Elite Motorsport, +0.122s
4. Gianmarco Pradel, Rodin Motorsport, +0.174s
5. Nikita Johnson, Hitech TGR, +0.200s
6. Keanu Al Azhari, Hitech TGR, +0.213s
7. Reza Seewooruthun, Argenti with Prema, +0.517s
8. Kai Daryanani, JHR Developments, +0.521s
9. Noah Lisle, JHR Developments, +0.557s
10. Alex Ninovic, Rodin Motorsport, +0.657s
11. Lucas Fluxa, Argenti with Prema, +0.763s
12. Stefan Bostandjiev, Fortec Motorsports, +0.876s
13. Yuanpu Cui, Argenti with Prema, +1.034s
14. Abbi Pulling, Rodin Motorsport, +1.064s
15. Jack Sherwood, Xcel Motorsport, +1.270s
16. Hugo Schwarze, VRD Racing, +1.536s
17. Bianca Bustamante, Elite Motorsport, +1.550s
18. Flynn Jackes, Elite Motorsport, +1.590s
19. Divy Nandan, JHR Developments, +3.699s