By Kymberlee Gomes of RNZ

On Anzac Day, most shops need to stay shut for the first half of the day till 1pm.

There are just three-and-a-half days a year which the Shop Trading Hours Act 1990 prevents most shopping - Good Friday, Easter Sunday, Christmas Day and the first half of Anzac Day.

What's open?

Exemptions apply to a few establishments that can open:

certain kinds of shops (limited to small grocery shops, pharmacies, service stations, takeaways, bars, cafes, duty-free stores, shops providing services (and not selling things), real estate agencies, public transport terminals, souvenir shops and exhibitions "devoted entirely or primarily to agriculture, art, industry and science". select places like Carnegie Centre in Dunedin or Mariners Mall in Picton if a cruise ship is in port among a few others (full list here). Shops covered by area exemptions cannot change them, and no new exemptions can be granted.

Shops without exemptions must stay closed during the first half of 25 April.

Mondayisation does not affect shop trading restrictions, because they only apply to the calendar date of Anzac Day.

Retailers can be fined up to $1000 if they open illegally.

Read more: Explainer: Why do we commemorate Anzac Day?

As for buying liquor, some bars, cafes and restaurants can continue to sell alcohol, as long as it is accompanied by a meal.

Surcharges

Cafes and restaurants can choose if they want to add a surcharge for opening on the morning of Anzac Day.

The surcharge covered the additional cost of wages on a public holiday, Restaurant Association chief executive Marisa Bidois said.

"Typically surcharges range from 10-15 percent.

"Some businesses incorporate the extra costs of operating on public holidays into their annual operating expenses. This approach allows them to spread the recovery of these costs over the course of the year, rather than imposing a surcharge specifically on public holidays," Bidois said.

Whether cafes opened on Anzac morning would depend on their location and customer habits, she said.

"To avoid surprises, diners should confirm whether a surcharge applies either ahead of time or upon arrival. Most establishments will inform customers of any additional fees through visible signage," Bidois said.

The Commerce Commission has also said establishments must make it well-known to customers that a surcharge will be payable before they decide to purchase or engage the service.

"It must be clearly disclosed, for example, by adding information to their website for online sales or placing a sign outside," it said on its website.

"In addition, the reason for any surcharge must be accurately described and must not be capable of misleading consumers. The surcharge should not exceed those costs, and the costs should actually be incurred by the business."

Main image (Unsplash/Rod Long): Shops without exemptions must stay closed during the first half of Anzac Day.