Business owners are being warned not to open today

Christmas Day is a restricted trading day, meaning almost all shops must be closed - unless they have an exemption.

MBIE's Head of Labour Inspectorate Simon Humphries says if someone does open, the 'occupier' of the shop may be liable for a fine of up to a thousand dollars.

He says people will still be able to get the basics from the pharmacy, dairies and small superettes.