The Warehouse is proposing to cut the jobs of 180 people across 93 stores.
Staff were told on Thursday about a proposal which it is believed would alter the lower tiers of its management structure.
The chain has a store manager, assistant store manager, team leaders and supervisors in each store. The proposal is to simplify this.
Team leaders would be replaced by a manager and supervisors by a second-in-charge.
First Union organiser Kate Davis said the move was baffling
"We do not want this to go ahead. Other retail companies are thriving. It suggests to us that the new company bosses just don't know how to do business in New Zealand. It's now a far cry from the red shed we all know and used to love. Tindall's work was fantastic but make no mistake; this is just about the opposite of what he set up. "
The Warehouse reported sales in the third quarter of its financial year of $388.3 million, down almost 1 per cent on the same time last year
"What we do know is that supervisors tend to be the older career retail workers who have solid hours... Those familiar faces people know at their local red shed will be gone, they are the ones who will be made redundant."
She said the retailer seemed to want to move to part-time staff on minimal wages.
"We have also seen a rise in the use of students who earn NZQA credits instead of money working at the store, and some of the most vulnerable in society, those receiving assistance from the government, work for free at The Warehouse to gain experience."
A spokesperson for The Warehouse said it was only a proposal at this stage.
It had been developed with input from store managers and feedback would be sought before the next steps were decided on. "It's not appropriate to comment further at this point."
Workers were given 10 days to reply to the proposal but the union has asked for longer.
