The guards were servicing an ATM in Athlone on Saturday morning when they came under attack, it said.
Western Cape police said five armed, unknown suspects made off with an undisclosed amount of money on the corner of Klipfontein and Carnie Roads.
Sergeant Noloyiso Rwexana said detectives were working around the clock, combing for clues.
SBV’s South African CEO, Mark Barrett said: “I am deeply saddened that one of our employees has lost his life during the attack and that another employee is in a critical condition.”
He extended condolences to the family of the deceased and wished his colleague a speedy recovery.
“I also wish to commend our team for their bravery in defending this violent attack.”
Barrett said he was horrified by the ongoing violent attacks against those in the industry.
The reward was for information leading to the successful arrests and conviction of the perpetrators.
The public could submit their information to the SBV Early Warning Robbery Hotline at any hour on 083-408-7029, and to the SAPS hotline on 10111.
