Waikato are the men's champions, while Manawatu have taken out the women's title at the National Sevens Championships in Rotorua.
In what was a tight finish to the decider in the men's competition, Waikato claimed a 21-17 victory against Tasman.
Manawatu prevented a Waikato double in what was also a close encounter in the women's final, prevailing 17-15.
The match for the men's silverware came down to the final play, after Tasman scored through Tone Ng-Shiu with just seconds remaining to close the gap to four.
Waikato, though, were able to secure the kickoff and kicked the ball into touch to secure victory.
The Mooloos had held a 14-5 at the end of a first half where it was Tasman who opened the scoring through skipper James Lash.
Tries to Sevu Reece and Tyler Campbell then put Waikato ahead at the break, only for Glen Ballam to cross in the corner for Tasman to make it a two-point game midway through the second half.
Waikato's third try to Sayarvat Srisawat looked to have sealed the deal, but Tasman kept fighting and Ng-Shiu's five-pointer meant the contest was not decided until the kickoff was claimed and hacked into touch.
The women's final was similarly hard fought, Manawatu scoring through Rhiarna Ferris and Janna Vaughan and Waikato replying through Stacey Waaka to give Manawatu a 12-5 lead at halftime.
Waikato started the second spell well, tries to Chyna Hohepa and Ariana Bayler giving them a three-point buffer at 15-12.
But a Manawatu side featuring several Black Ferns were not to be denied and with only seconds to play the pace of Lauren Balsillie proved crucial as she dotted down in the corner to secure her side the title.