Car insurance premiums for women are up 15 per cent, or £114, ahead of new EU gender rules kicking in next week.
The average best price for female car insurance premiums has risen from £748 on November 1 to £862 on December 12 according to comparison site Gocompare.com.
With a week to go until the European Court of Justice ruling on gender equality comes into effect, it has long been reported that female insurance premiums would rise to bring them in line across the board, despite statistics which show women drivers have less accidents than their male counterparts.
The comparison website has analysed more than 10m car insurance quotes since January 2011, but says this is the most significant movement in premiums to date. Along with the 15 per cent increase for women, there has also been a slight increase in the best price for 17 and 18 year old females from £1,910 at the start of November to £2,921.
Meanwhile, black box car insurance brand Ingenie, which insures 17-25 year olds, sees the ruling as a "step closer to a future where all young drivers are treated as individuals, with premiums based on how well they drive".
Chief executive Richard King said: "As a specialist brand for young drivers, we know that teenage drivers in particular are often offered expensive quotes - but this isn't always fair. Our experience is that many of our customers actually drive really well.
Gocompare.com's head of motor insurance Scott Kelly added: "With the majority of insurers saying they are leaving full equalisation until the last minute we are not going to see the real impact of the ruling on the best prices available until December 21.
"One impact could be that the number of insurers offering cover for drivers of certain ages will fall as companies temporarily exit the market until prices settle down and they can then pick their price points.
"We still don't know exactly how the market is going to look post December 21, but the assumption is that rates for female drivers will continue to rise."
The change in the law comes into force from December 21, 2012.