The packaging manufacturer has begun a 90-day consultation process with affected employees, although a final decision on the proposed closure has yet to be made.
Nampak said the restructuring was part of an investment programme that it hoped would enable it to maintain a competitive edge and become the lowest-cost packaging producer in the UK.
In a statement, the company said the potential closure would not result in a reduction of capacity, but a more "efficient and streamlined operation with lower costs".
It said: "Nampak Cartons has completed a review of its UK operations with a specific focus on increasing efficiencies and technological improvements."
Nampak hopes, by focusing on the most modern factories that offer the most efficient production facilities, it will stay ahead of the changes within the industry.
Job fears as Nampak considers closure of Somerset site
Nampak is considering closing its Crewkerne factory in Somerset and reorganising administrative roles at its Gillingham site in Kent, putting up to 125 jobs at risk.
