Census figures have shown that 50% more people are leaving the Six Counties for the rest of Ireland than made the return move last year.
The number of people moving North from the 26 Counties is almost five times less than the total arriving into the Six Counties from Britain.
Almost 19,000 people moved to the Six Counties in the year before the 2001 census and just 2,319 of them came from the 26 Counties. Figures from the 26-County census indicate that 3,491 moved South from the North in a 12-month period.
The figures reveal the social, cultural and economic divide between the North and South which continues to loom large in the minds of Irish people.
The migration flows between the north and Britain are "broadly in balance", according to Northern Ireland Statistics and Research Agency, with those moving to England, Scotland or Wales totalling 12,479 and the arrivals numbering 11,539.
Demographic expert Piaras MacEinri from the geography department at the University College Cork said that despite paramilitary ceasefires, the Good Friday Agreement and various initiatives, there had not been enough people-to-people contact.
This has led to a "gulf of understanding" which in turn discourages people from moving to the North from the South, he added.
"There is a perception that the Celtic Tiger effect didn't cross the border," Mr MacEinri said.
"Then there is the historical fact that most southerners are profoundly unconcerned about what happens in Northern Ireland."
The geography lecturer said the reluctance even to visit the north was more than "a political point".
"It's an image problem too. Southerners are self congratulatory. We think we've moved into the 21st century and Dublin is so cosmopolitan but that the same is not true for Belfast or Derry."