The number of shoppers leaving Donegal to cross the border may have risen as much as 20 per cent in recent weeks due to the plunge in the value of sterling.
A quarterly survey of the percentage of Irish-registered cars in a selection of border-located shopping centre car parks in Northern Ireland has reached almost 57 per cent.
It is the first cross border shopping survey carried out by Inter Trade Ireland since a plunge in the value of sterling in October, which saw the value of euro rise to 90 pence.
The survey for the third quarter of the year, saw an increase from 37 per cent in the third quarter of last year.
The occupancy rate in the second quarter of this year, before the drop in sterling, was 43 per cent.
Inter Trade Ireland says the figures have proven to give an accurate indication of the peaks and troughs of cross-border shopping activity.
The end of 2008 saw the highest percentage of Irish registered cars (67 per cent) in shopping in centres in Northern Ireland.
Every Christmas season since has seen an uplift in the numbers of Irish-registered cars followed by sharp declines in Q2 and Q3. Since the beginning of 2014 the share of Irish-registered cars in NI shopping centres has remained below 50 per cent.
The slide in the value of sterling against the euro since Q2 2015 has begun to make cross-border shopping more attractive again. The share of Irish-registered cars in border shopping centres has risen from 33 per cent in Q1 2016 to 43 per cent in Q2, even before the result of the Brexit referendum was known. With the subsequent 10-12 per cent rise in the value of the euro against sterling, Q3 2016 has seen a further increase to 56 per cent in flows of cross-border shoppers.