Jos Buttler's men take on the Proteas at the Ageas Bowl in the third and final match of their Twenty20 series.
England won the opening match with a 41-run success in Bristol, as Moeen Ali and Jonny Bairstow turned on the style for the hosts.
South Africa came back strong in Cardiff as they powered to a 58-run victory, with Rilee Rossouw producing a scintillating performance having scored 96 not out.
The series decider takes place this Sunday, with the start time scheduled at 2.30pm BST.
However, over at Wembley Stadium, England's Lionesses face Germany in a historic Euro 2022 final at 5pm.
Despite the clash, the England and Wales Cricket Board has decided against altering the start time at Southampton.
"Like the whole nation we're wishing the Lionesses all the very best in the final on Sunday and will be rooting for them," said an ECB spokesperson.
"Anyone wanting to keep up to speed with the football while attending England men's IT20 clash against South Africa at the Ageas Bowl will be able to see it on the concourse televisions or in the Lakeview Restaurant."