Another supplier who transported the meth with Smith, Jonelle Rachel Phillips, also appeared in court this morning.
Much of the dealing was done out of a house in Tawa.
In total, Smith supplied about 15kg of meth, which was supplied throughout the region over about six months. The drugs had an estimated cost of $5.25 million.
Crown prosecutor Emma Light said Smith was "not merely a courier" for the drugs, but was in fact a "crucial link".
But Smith's lawyer, Maria Pecotic, said he was simply "the perfect person for the main person to hide behind".
"He's the delivery boy . . . the Crown have promoted Mr Smith to too high a level.
"The actual main organiser likes to keep themselves arm's distance away."
She said it was a good opportunity for the main offender, then, to use a man who had "never really been in trouble", owned a business, was not a gang member, and had a "raging drug addiction".
Pecotic said Smith was not involved for financial gain, but because he became "caught up in a whirlwind of methamphetamine use".
Justice David Collins said Smith had seven previous convictions, but they were not for serious offending and were historical, with the most recent conviction being in 1997.
He sentenced him to 13 years and six months in prison, with a minimum non-parole period of six years and nine months.
Phillips, who was sentenced directly after Smith, had pleaded guilty to three counts, including one representative, of supplying meth, and one count each of supplying cannabis, possessing meth for supply, possessing a class B drug, and possessing cannabis for supply.
Pecotic said Phillips' offending was fuelled by "gruelling" incidents in her past, which led to her own drug addiction.
She has been diagnosed with post traumatic stress disorder since the offending and is receiving ACC treatment.
Phillips knew there was meth in the car when she drove to Wellington with Smith, but offended out of a "sense of blind loyalty", Pecotic said.
Justice Collins said he was satisfied that was the case, and that Smith would have offended whether Phillips went with him or not. The pair were in a relationship.
Intercepted phone conversations revealed Phillips was dealing drugs to other people as well.
She has 13 previous convictions from 2011 for conspiring to deal meth.
Justice Collins sentenced her to four years and three months in prison.