Some Auckland supermarkets are restricting entry today, due to unusually high numbers of shoppers.
The supermarket rush coincides with the confirmation of the first coronavirus case in New Zealand.
One Auckland supermarket manager told RNZ they noticed a surge of customers after the confirmed case was announced last night. They said many people were purchasing toilet paper, hand sanitiser, and tinned food.
In a statement, Foodstuffs said some supermarkets were limiting the number of people in-store at any one time.
"This decision is being made for the safety and comfort of customers, and will be utilised for short periods as needed.
"If customers continue to shop normally, stores will have no issues providing the usual range of products. We would ask customers to resist the urge to stock up as this simply puts unnecessary pressure on stores."
Some stores could be completely out of stock of hand sanitiser and face masks and others could have quantity limitations in place, it said.
"We are continuing to work closely with vendors to secure as much stock as possible, and exploring sourcing new brands to fill the gap, but volumes are limited due to international demand.
"If a customer's local store is sold out of the antibacterial products they are looking for, we ask for patience as we secure more stock and get it on store shelves."
One customer, Paula Korunić, visited Pak 'n Save in Royal Oak at 8am today.
Crowds of people were purchasing toilet paper, hand sanitiser, and tissues, she said.
"The main entrance was locked... because they were letting in groups of about five people at a time, because the supermarket was essentially at capacity because of people panic buying."
Lots of people were rushing around inside and queues at the checkout were very long, she said.
Countdown supermarkets declined to comment.
Director-General of Health says no need to stockpile
The Director-General of Health, Dr Ashley Bloomfield, said there is no need to stockpile food and emergency supplies now that Now Zealand has one case of coronavirus.
Since a person tested positive for coronavirus in Auckland yesterday, people have been seen buying masks and things like toilet paper, hand sanitiser and tinned food.
But Dr Bloomfield said he had spoken to the Food and Grocery Council and there are plenty of supplies to go around.
"I think what people need to do is again, just keep this in perspective, it's a single case, yes prepare, make sure you've got what you need, but there's no need to make sure that you have everything stocked up in the cupboard by the end of this weekend."
Dr Bloomfield said masks can help to protect from germs, but people need to avoid touching their face while wearing them.