Champion Green founder Marian O'Gorman has welcomed the dramatic increase in shopping locally as a tremendous boost for the Irish economy.
Ms O'Gorman said it was encouraging shoppers to keep money in circulation locally, as "non-essential" retail outlets reopened for Christmas trading this week.
Retail Excellence has predicted that €6 billion will be spent in retailers during December.
While it will not make up for the losses incurred during the six-week lockdown, the strong surge in championing Irish retail is very welcome, Retail Excellence said.
Christmas trade, which can start in September, represents up to 50% of annual turnover in some sectors, according to Duncan Graham, the chief executive of Retail Excellence.
Figures for online retail over the Green Friday weekend show that spending on Irish websites more than doubled over the regular Christmas shopping launch weekend and increased by 135% on an annual basis.
New figures show that 39% of all online spending by Irish Revolut users on Green Friday - November 27 - went to Irish websites, while 61% went to international retailers.
This marked a significant shift to buying Irish online, compared to last year, when just 28% of online spending went to domestic websites.
Meanwhile, An Post has said that half of the parcels it now handles in the new online shopping boom are from Irish retailers.
Champion Green is a nationwide consumer marketing initiative backing local jobs and enterprise.
Founded by Kilkenny Design, it is supported by Visa, as well as business groups Retail Excellence, the Small Firms Association and Chambers of Commerce Ireland.
Marian O'Gorman said the Covid pandemic had shaken many small businesses and Irish producers, but added that one positive out of all the setbacks is that community is now stronger.
"People realise that supporting each other and local business is critical now, if we are to recover from this huge economic and social challenge. As the festive shopping rush begins, I would encourage consumers firstly, to stay safe, and secondly, to make shopping local a priority," she said.
Ensuring that Christmas spending stays in the local economy will make a real difference, Sven Spollen-Behrens, Director of the Small Firms Association said.
"The extent of online shopping with local retailers for Green Friday was encouraging. We need this to continue now, instore too, and for households to consciously look at dealing with locally owned firms for all of their household and family product and services," the SFA director said.
"Small businesses are the cornerstone of towns and communities across Ireland, and the coming month will be crucial to their recovery," he added.