Up to 750 jobs could go in the proposed restructure of The Warehouse, the company's chief executive officer says.
Staff were called to an 8am meeting today to hear the company's plans.
In a statement, chief executive officer Pejman Okhovat said the restructuring will mean cutting 500 to 750 jobs.
If confirmed, the job losses would be the equivalent of 320 full time roles, he said.
Okhovat said the restructuring was necessary because of changing shopping habits and the growth in online sales.
The announcement did not make clear whether The Warehouse Company's two other chains, Noel Leeming and Warehouse Stationery, would be affected.
First Union accused the company of using Covid-19 to justify the redundancies.
It understands four stores will close if the proposal is adopted.
"They've been reviewing their business for years and the pandemic has accelerated their progress on an 'agile' system that means workers lose out, communities lose jobs, and customers get a worse experience shopping there," First Union general secretary Dennis Maga said.
"The restructure includes sweeping reductions of hours across the country that are left to individual store managers to find and cut, as well as hundreds of job losses and the closure of physical stores."
Last month, The Warehouse Group chief executive Nick Grayston said the company was adopting an agile working structure, which could see more than 1000 jobs cut across the country - nearly 10 percent of the work force.
At the time he said it could see six stores close across the whole Warehouse group - Noel Leeming in Henderson and Tokoroa, The Warehouse stores in Whangaparaoa, Johnsonsville and Dunedin Central, and Warehouse Stationery in Te Awamutu.
Prime Minister Jacinda Ardern said she was "angry" at the proposed job cuts and expected The Warehouse to do more to keep staff employed.
The Warehouse has been paid about $52 million in Covid-19 wage subsidy.