Central Auckland businesses face a "grim day" as smoke closes public facilities and many commuters are staying at home.
Auckland Council, the Auckland District Court, the Central Library and the City Art Gallery have closed for the day because of the SkyCity convention centre fire.
Farmers' Queen St department store is closed, but Smith and Caughey remains open.
Heart of the City chief executive Viv Beck said most small businesses in the central city "would be in a position of needing to open" but there were few customers on the streets.
"It will be a pretty grim day for them, I would say. I think it's going to be a pretty quiet day with people not coming in if they don't have to," she said.
"It's pretty dark. It's a combination of bad weather and there is quite a lot of smoke around."
About 1800 staff who normally work in Auckland Council's Albert St and Federal St buildings were told at about 6.30am today to stay at home for the day because of the toxic smoke contaminating the area around the fire.
The District Court and Chorus House are "closed until further notice for public safety as a result of air quality issues".
A notice on the court website advises those scheduled to attend court to call 0800 COURTS for further information.
"The High Court is not affected by this closure at this stage. We will update you as soon as we have further information," it says.
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Auckland Council said the Central Library and the Auckland City Art Gallery would be closed today.
Bledisloe House, which houses some council and central government offices, is "open for essential services only".
WorkSafe's central city Auckland office is closed today due to the fire.
A notice on its website says: "During this time, if you need to make a notification, please email email@example.com."
SkyCity itself is closed.
"We have made the decision not to open today, but expect that we can open our facilities tomorrow, once the smoke has cleared - that includes the Sky Tower, Casino, Convention Centre, hotels and restaurants," the company said.
"The SkyCity carpark also remains closed, if your car is still in the carpark, we apologise for the inconvenience and we will communicate as soon as we can release those cars."
However, the Aotea Centre remains open and some events have been transferred there from SkyCity.