Primark plans to move 220 jobs from its head office in Reading to the company’s international headquarters in Dublin.
The retail giant is moving its buying, merchandising, design, quality and sourcing operations to Ireland from September.
The company said the the decision was about “driving operational efficiency” and nothing to do with any external factors such as Brexit.
Employees affected by the changes will have the opportunity to work in Dublin.
Lorraine Culligan, group director of people and culture, said: “Our colleagues will be fully supported during this period of change.
“Primark’s office in Reading continues to play a vital role in our business and many of our teams across a number of core functions will continue to be based there.”
The company’s “product operations” are currently separated across Dublin and Reading and the office in the Berkshire town will remain open.
Primark CEO Paul Marchant said the changes would “ensure our business strategy and our expansion into new international markets is fully supported”.
Community interest company Reading UK’s executive director Nigel Horton-Baker said the announcement was “sad news for those staff affected, particularly if their personal circumstances mean they are unable to relocate to Dublin”.
However, he said it was “not a Honda moment”, referring to the closure of the Swindon car plant.
Mr Horton added: “They are just completing the fit out of their 5,000 sq m UK head office building in Reading town centre and more than half of their 500 staff will continue to work in Reading.”