The Black Caps made 177 for seven after winning the toss and batting in the second and final 20-overs contest between the two teams on New Zealand's short tour.
The total was four runs better than New Zealand?s previous highest against South Africa -- 173 for four at Hamilton in 2011/12. New Zealand lost that match by eight wickets and the tourists may have felt they again had not taken full advantage of ideal conditions.
As in the first match in Durban on Sunday, Guptill and skipper Kane Williamson got the side off to a fast start, putting on 52 off 5.3 overs before Williamson was caught at third man off Kagiso Rabada for 25.
With Guptill making his 60 off 35 balls, New Zealand put up a better performance on Sunday but again there were no further major partnerships.
Fast bowler Rabada took three for 30, including two wickets off successive balls in the penultimate over.