The Alliance Group says it was a tough decision to close its Christchurch meat plant, resulting in the loss of about 250 jobs.
The company signalled in September that it was considering closing the plant in the middle of next year, when its killing season comes to a close.
It has now confirmed the closure but says it will offer staff jobs in its other plants.
Chief executive Grant Cuff says the plant has been making losses in recent years and the decision to close it became inevitable. They're very proud of all their staff, he says, and "it's never something that you wish to do".
Mr Cuff says the Canterbury earthquakes were not a contributing factor: the company had been considering its options before the quakes struck.
Meatworkers' Union spokesperson Dave Eastlake says jobs will be scarce for the affected workers, and they may have to move out of the area or commute.
But Mr Eastlake credits the Alliance Group with giving workers plenty of notice of the pending closure.
The company says it will offer Sockburn staff employment at its other plants.