New Zealand won the Sevens World Series for the ninth time on Sunday despite suffering a 42-19 semi-final loss to Fiji at Twickenham.
New Zealand failed to reach the final for just the third time in eight events this season.
But the performance was still enough to secure an unassailable lead over England in the overall standings.
England lost 19-17 to Kenya in the Bowl quarter-finals but beat Portugal 22-7 in the Shield final.
South Africa ended the Fijians' hopes in the main final, winning 24-14 to add the London title to the USA Sevens crown they won in February.
Having ended Australia's defence of the London title in the quarter-finals and beaten Rugby World Cup Sevens champions Wales 21-19 in the semis, South Africa outscored Fiji by four tries to two, with Bernado Botha touching down twice.
Samoa's Tom Iosefo finished as the tournament's leading try scorer with 10 after scoring two in a 22-12 win over Australia in the Plate final, while Scotland edged Kenya 21-19 to take the Bowl.