The Slovakia unit's results would be reported separately from Biedronka, chief financial officer Ana Luisa Virginia said, adding that it was premature to provide any guidance for investment and sales of the unit.
"We are talking about an operation done from scratch, we are not disclosing much," she said on a conference call with analysts.
The company's interest in the central European country was first reported in March, when the head of the Polish unit Biedronka, Luis Araujo, said that many Slovak consumers were already crossing the border to buy at Biedronka, and the company had been "looking carefully at Slovakia" for expansion.
Besides Portugal and Poland, Jerónimo Martins is present in Colombia, where it operates a store chain called ARA.
The CFO did not rule out a potential expansion to Romania – a market that has been on the company's radar for years – but noted it was not a priority.
"It would only be (a priority) if we decided that we would have the right target at the right price," she said. "Currently, we want to concentrate on Poland, on ARA. So, it's not really a priority."
Jerónimo Martins reported a 28% jump in third-quarter net profit, driven by a robust increase in sales at Biedronka, although its profitability narrowed slightly on cost inflation and discounts.
According to JP Morgan analysts, the results were better than feared at Poland's market leader Biedronka, which justified the rebound in the shares following recent underperformance.