Research by Intertrade Ireland, the cross-border trade and business development body set up after the Good Friday agreement, indicates that 95% of companies here still do not have a formal plan on how to deal with Brexit.
Intertrade's latest quarterly business monitor is based on a survey of over 750 small and medium sized companies across Ireland.
According to the survey, one in three exporters said they have experienced negative consequences already due to Brexit.
But despite Brexit concerns, InterTrade's latest quarterly report indicated a picture of a buoyant economy with 39% of businesses in growth mode and a further 57% in a stable position.
It also revealed that companies trading cross-border are faring particularly well, with 50% enjoying growth.
But that growth is not translating into a similar upsurge in employment, with only 7% of companies reporting that employment levels have increased over the past quarter.
Cost increases in overheads and through the supply chain are also major challenges facing companies, InterTrade Ireland said.
Aidan Gough, Strategy and Policy Director at InterTradeIreland said that a buoyant economy should not distract from the need to confront and prepare for challenges that lie ahead especially in terms of dealing with rising costs, skills shortages and potential changes to trading relationships.
"Our latest Business Monitor shows that over 70% of businesses are operating on very tight margins (below 10%) and therefore carry a high exposure to rising costs," he added.
