353 out of the 357 kilograms was intercepted in Auckland.
Drug Foundation CEO Ross Bell said the surge can be put down to a flexible drug market.
"Increasingly we're seeing a move away from methamphetamine being manufactured in New Zealand...a few years ago we saw ingredients for methamphetamine coming across the border," he said.
Addiction Treatment National Committee Chair Dr Vanessa Caldwell said the surge in seizures isn't being felt on the streets.
"Certainly the communities are telling us that it's easy to get on the streets and it's very prevalent."
"There's still some getting through."
Interceptions of ingredients for methamphetamine drop
While methamphetamine interceptions have skyrocketed, the amount of P ingredients being found has dropped.
In 2009, more than a tonne of pseudoephedrine was stopped by Customs. So far in 2016, just over three and half kilos has been found.
But seizures of ephedrine, another ingredient for the manufacture of P, has risen. In 2009, almost 96 kilos of the product was stopped.
This year, that leaps to more than 760 kilograms. And in 2015, more than 900 kilograms was seized.
Staff numbers drop
In the same period, from 2009 to 2016, the number of operational Customs staff has dropped from 572 to 501.
The majority of those 71 losses were in Auckland, where 53 people lost their jobs.
Ross Bell said the reduction is probably down to better technology.
"New screening devices at the border, better intelligence gathering, they know now what to look for in the mail."
