He is set to become the most expensive goalkeeper ever, beating the €72.5m (NZ$125m) Liverpool paid Roma for Alisson earlier this summer.
The Spain worldwide has been regarded as one of the best upcoming shot-stoppers in Europe and the Blues have supposedly reached an agreement to sign him amid the uncertainty surrounding Thibaut Courtois' future.
"Kepa is a talent we have admired for a long time and we are extremely excited about his arrival", she said.
"It's been a very important decision for me", he said.
"It is an accumulation of things really and I am delighted that the club has signed me".
The 24-year-old Croatia global arrives at Stamford Bridge with a big reputation, but there is no official option for Chelsea to make the move permanent after the 2018/19 season.
A move to Real Madrid will mean a return to Spanish football for Courtois, who played for Atletico Madrid before becoming Chelsea's number 1.
Real Madrid confirmed Courtois will undergo a medical on Thursday morning before signing a six-year deal.
The Oscars Are Changing Because You Aren’t Watching
But Wednesday's announcement means there are more opportunities for those films to be recognized during Hollywood's Biggest Night. The next Oscars ceremony will take place in Hollywood on February 24, as previously announced.
Pornanong singing to keep lead of Women's British Open
In 2017, Hall returned to the Women's British Open to finish in tied-third, a high she matched in the World Ladies Championship. Phatlum found trouble at the 17th and missed a short putt for bogey to give Hall a three-stroke lead with one hole play.
Over 500 hikers rescued on Bali's Lombok
Hundreds of people in Lombok have been left homeless and are staying in temporary camps amid continuing aftershocks. A Malaysian was among the dead, with another six citizens injured, the foreign ministry in Kuala Lumpur said.
In Women's Heart Attacks, a Doctor's Gender Matters
Women doctors, in 2017, earned 27.7 percent less than their male counterparts, an average of $105,000 less a year. But when female physicians took charge of treatment, those percentages fell - to 11.8% of men and 12% of women .
How Nasa will attempt to ‘touch the Sun’
At its closest point, the probe will come within 4 million miles of the star's surface, placing it within the corona . This means that if it doesn't launch on the 11th, there will be other opportunities for launch up until August 23.
Congo's health ministry confirms 3 more cases of Ebola
Nearly 1000 people who have had "contact" with the virus have been registered in health zones under surveillance, it said. The area comprises one million displaced people and shares borders with neighbouring countries of Rwanda and Uganda.
Samsung Begins Mass Production of 4-Bit 4TB SSD for Consumers
A new round of NAND flash production at Samsung could finally make SSDs in the multi-terabyte range affordable and mainstream. A major impediment to making 4-bit NAND a reality has been the substantial performance hit due to lower charge levels.
Transfer: Arsenal finally accept £4.4m offer for striker
West Brom have emerged as surprise contenders in the race to sign Fiorentina midfielder Carlos Sanchez, with West Ham also keen. The 29-year-old has signed a three-year deal with the Hammers, having spent the last two seasons with the Gunners.