Food, beverages, health and sanitary products and toiletries are what constitutes essential goods that can be purchased online.
Couriers will not be able to deliver anything other than these essential items.
"Couriers will only be delivering essential items. We are asking customers to commit to only purchasing essential items at this time," a spokeswoman for MBIE said.
Deputy chief executive for MBIE Paul Stocks told Newstalk ZB's Heather du Plessis-Allan that people will not be able to buy non-essential products online during the lockdown.
"You won't be able to order a nice new t-shirt," Stocks told du Plessis-Allan.
"We are not expecting the sale and delivery of non-essential items will be proceeding under level 4," he added.
Mobile phone and computer repairers are classed as essential and may continue to work but, where possible, have to do it from home.
If they work from their commercial premises, they must keep personal interactions to a minimum.
Vodafone NZ has confirmed it will be able to continue selling phones and Sim cards via its website.
MBIE is working through details on how people can get other items, such as home appliances, repaired.
Trade Me has updated its users that, as of today, couriers can only take bookings from essential businesses.
"This is an evolving situation and our courier partners have informed us today that they can only take bookings from essential businesses," Trade Me wrote on its website.
"This means that members won't be able to buy your item(s), however they can still bid, browse or save items to their Watchlist."
