The Champions Trophy winning skipper will be replacing Australia batsman Peter Handscomb who is scheduled to attend a training camp ahead of the Baggy Green tour to Bangladesh.
Handscomb may yet not attend the camp if the Cricket Australia pay dispute is not resolved soon with negotiations still ongoing.
Yorkshire’s other overseas professional, they are permitted two for the Blast, is another Australian, Shaun Marsh.
Marsh has not been selected for the tour to Bangladesh and should be able to compete in the entire competition.
The signing of Sarfraz has been made pending a work permit for which the wicketkeeper batsman has applied.
Handscomb has been performing the wicketkeeping duties for the Blast with first choice keeper Jonny Bairstow on England duty so Sarfraz serves as a perfect replacement.
Sarfraz led Pakistan to victory in a one-off T20I against England last year and has been in terrific form with the bat.