Auckland Mayor Phil Goff is urging businesses to stop price gouging and "act responsibly" as the city enters its fourth day in level 3 Covid-19 lockdown.
Goff said he has heard reports of price gouging, especially essential items such as masks.
"We had similar concerns during the last lockdown and it would be unfortunate to see a repeat this time around."
There were similar claims during the nationwide lockdown.
In March, the Herald reported Prime Minister Jacinda Ardern had set up a website for New Zealanders to raise concerns about supermarkets raising prices during lockdown.