Westland Milk Products finished the season with an increase of more than 5% in milk production, despite the serious drought in its main supply area.
The summer drought knocked national milk production for the 2012-13 season by 2%.
But Westland chief executive Rod Quin said West Coast farmers produced about the same amount of milk as the previous season.
Milk supply from irrigated Canterbury farms, unaffected by the drought, also helped.
