Organisers of this year's protest for cannabis law reform are citing a wide range of supporters.

Events are planned around New Zealand for J Day today. J Day is a worldwide protest against prohibition of cannabis and attendees often light up.

"For the first time there are multiple parties contesting the election who advocate for cannabis law reform," says national coordinator Chris Fowlie.

"The Greens have been joined by Labour and the Maori Party, as well as ACT, TOP and the Cannabis Party. Even United Future is on the side of reform!"

He says cannabis should be a health issue, not a crime, and there are too many cannabis users to arrest.

"One in 20 Kiwis use cannabis medicinally. They need safe and legal access to affordable natural cannabis and medical products, including the right to grow their own medicine," Mr Fowlie says.

NORML wants a regulated taxable market for the adult use of cannabis and says other countries already have it.

Treasury estimates this would save $300 million in policing costs while raising an additional $500 million in revenue, Mr Fowlie says.

J Day events are planned in Whangarei, Auckland, Hastings, Taupo, Wellington, Nelson, Christchurch, Dunedin and Invercargill.