The 24-year-old will start from 12th on the grid at Silverstone after taking advantage of changeable conditions on Saturday.
However, Bianchi insists that the long-time Formula 1 backmarkers made the right calls during qualifying, including a late switch to dry tyres.
He told reporters: "A fantastic day for the team and I'm so happy for everyone. After our first points in Monaco, it's great that we have now achieved the team's best ever qualifying result.
"Today's situation was not easy and so this result is down to a combination of great strategy, judging the changing conditions to perfection and then just making the most of the windows we had out on the track when the conditions were right for the tyres.
"It was a real gamble, but we had everything to gain from taking some risks, so for the last run we put the slicks on even though the track was right at the limit."
Bianchi's teammate Max Chilton was 13th fastest in qualifying, but will start from 18th on Sunday after taking a five-place grid penalty for a gear box change.