New figures indicate that 250,000 households in the Republic are now crossing the border to Northern Ireland to do their shopping.
The figure is an increase of 50,000 on the number quoted by the research group TNS Worldpanel for last year.
Another survey by Nielsen Ireland suggests that off-licence sales in Northern Ireland are up 30% but are down 7% in the Republic.
Director of the Alcohol Beverage Federation of Ireland Rosemary Garth has called on the Government to review excise duties on alcohol.
