Manufacturing of the breakfast spread has been halted by earthquake damage to Sanitarium's Christchurch plant; the only plant where Marmite is made.
Sanitarium is urging consumers not to "freak out" as it works to move its Marmite manufacturing facilities to a safer part of the Christchurch site. But it is asking consumers to ration Marmite while supplies are spread thin.
Sanitarium general manager Pierre van Heerden said people should consider spreading it on toast rather than bread, as it spreads more easily and goes a little further.
Retailers' distribution centres and supermarkets still had some stock, he said.
"Certain sizes have totally run out, and last week ... we sent our last stocks out to the distribution centres of the retailers," he told Radio New Zealand.
But he urged consumers not to "freak out about it".
"We will get Marmite back, we will be producing it in New Zealand; it will be the same product that we've all come to love."
In Dunedin, St Clair Four Square owner Sandra Millar said she sold her last four jars of the spread to a single buyer just before 6.30pm yesterday.
Dunedin central city Countdown and New World stores were both out of stock last night.
Countdown referred inquiries to parent company Progressive Enterprises. A statement from merchandise general manager Murray Johnston said Progressive expected to run out of Marmite in the next two or three weeks across all stores.
