Williamson finished with 87 winners in the premiership which ended last Friday night.
His drives won $793,640 in prize money. He also collected 82 second placings and 71 third placings.
In something of a coincidence, Williamson drove 87 wins in the previous season when he finished fourth in the premiership.
Canterbury driver Blair Orange was a decisive winner in the harness driving category with 219 victories.
The harness trainers’ premiership went to Canterbury trainer Robert Dunn with 95 winners while Mark Purdon and Natalie Rasmussen gained 81 victories.
Lisa Allpress won her fourth jockeys’ premiership, bagging 95 winners.
She won last year with more than 130 winners, the Covid-19 shutdown having a big impact on the past season.
Trainer Jamie Richards, son of former Wingatui jockey and trainer Paul Richards, won his first premiership with 101 winners.
