Pretoria - The English Premiership league champions, Saracens, will play a full-strength Bulls team in London next January.
"The Blue Bulls are always formidable opposition, and we look forward to another fantastic occasion at Allianz Park," said the Saracens' Director of Rugby, Mark McCall.
"Our players greatly enjoyed the match against the Sharks in January.
These matches against top southern hemisphere opposition have become part of our annual calendar."
"Saracens are closely followed and well supported throughout South Africa," said Bulls coach Frans Ludeke.
"They have been performing really well in the Premiership and the European Cup, and might easily have won both competitions last month.
"We look forward to a great game on the artificial turf at Allianz Park."