Coles confirmed on Friday "several hundreds" of back-office roles would be made redundant, redeployed or workers retrained in a multi-year deal with professional services outfit Accenture.
The partnership aimed to strengthen specialist technological and digital capabilities it needed to continue supporting the business and serve customers, a spokesperson said.
The Australian Services Union slammed the announcement, saying the plan echoed a recent move by Woolworths to send finance, HR and IT roles to India and the Philippines.
"Coles wants you to believe sending hundreds of Australian jobs to India is about 'seamless, personalised digital experiences'," ASU assistant national secretary Scott Cowen said in a statement.
"What it's actually about is a company that made well over a billion dollars in profit last year finding new ways to spend less on the people who helped it get there."
Under the multi-year partnership, some roles in finance, human resources, marketing and technology would shift to Accenture's overseas and Australian offices, adding to the back-office services the consultancy already provided to Coles.
"You'd think a firm charging what Accenture charges could come up with more than one idea," Mr Cowen said.
"Apparently not: cut jobs here, do the same work for less somewhere else, call it a partnership, and hope nobody clocks that it's the same deal for the third time this year."
Friday's announcement came days after the Australian Financial Review reported Qantas was in advanced talks with Accenture to outsource 1000 jobs to India as it sought to cut costs and bolster its operations with artificial intelligence.
Qantas maintains that no final decision on the partnership has been made.
Coles said such decisions were never made lightly.
"We will redeploy as many affected team members as possible, including reskilling opportunities and pathways into other roles across Coles," the company spokesperson said.
The company claimed it would remain a net creator of Australian jobs as store numbers continued to grow.
"It's important to note that the changes affect a very small portion of the 115,000 Australians that Coles employs, and does not impact the vast majority of our team who work in-store, in communities across the country," the spokesperson said.