Adam Peaty won his third gold and Fran Halsall her second as Britain made it their most successful European Championships ever.
Peaty, who set a world record 26.62 seconds in the semi-finals, won 50m breaststroke gold in a time of 27.00.
Halsall edged out fellow Briton Georgia Davies by one hundredth of a second to win the 50m backstroke final in 27.81.
Britain have won six golds and 19 swimming medals in total and are top of the medal table, with one day to go.
|Swimming medal table: Top six nations|
Their previous best performance at a Europeans Championships was the 18 medals, including six golds, they won in Budapest in 2010.
In addition to 19 medals in the pool, open water swimmer Dan Fogg and diver Sarah Barrow have also won gold while Tom Daley's silver helped Britain into top spot in the overall medal table for all the aquatic disciplines.
City of Derby swimmer Peaty, 19, also won gold in the 100m breaststroke and the 4x100m mixed medley, and could win a fourth in the 4x100m medley relay on Sunday.
"I'm really happy with winning that one," he said of his 50m breaststroke victory. "It was a bit slower than my heats and the semis, but I was coming off a massive high last night - a high I've never experienced before.
"Hopefully come the Olympics I can fine-tune that and get stronger through the rounds."
Halsall, who does not count the backstroke as one of her main events, beat Commonwealth Games champion Davies to the wall with a personal best time of 27.81.
"I don't know how that happened," said Halsall. "It was just a fun event where I wanted to see how I could do.
"I was hoping to dip under 28 seconds, and I did that and managed to get a gold medal, so I can't complain.
"It's just on the day who gets their fingernails on the wall first and today it was me."
The 24-year-old, who won gold alongside Peaty in the mixed relay, will go for another medal in the 50m freestyle final on Sunday after qualifying second fastest.
Adam Barrett just missed out on a medal after touching in fourth place in the 100m butterfly.
Ben Proud progressed into the 50m freestyle final as the second fastest qualifier behind Olympic champion Florent Manaudou.
|BBC Sport commentator Karen Pickering|
|"Fran Halsall made a great start and threw herself at the finish. It just shows that if you have pure speed you can turn your hand to any discipline. She is having a summer that she will never forget."|