Northern Ireland trade to the Republic of Ireland is almost double that of what goes in the opposite direction, a new report suggests.
The report of cross border trade found that exports - excluding the financial and farming sectors - to the Republic were estimated to be worth £3.4billion to the Northern Ireland economy while imports were thought to be worth £2bn in a year.
The findings come in a report surveying the cross-border supply chain by the Northern Ireland Statistic and Research Agency (NISRA) which was commissioned by the Department for the Economy.
It found there were almost 1.2million cross-border deliveries in a year with nearly three-quarters of exports made by small businesses with fewer than 50 staff.
However, the overall figures are likely higher as only VAT registered businesses were included in the survey, meaning almost 60,000 small traders or those self-employed were excluded.
It is the first detailed report of its kind.
In a statement the Department of Economy said: "The new survey and analysis paint a rich picture of the web of cross-border connections and trade between Northern Ireland businesses and businesses and consumers in Ireland.
"This is, however, only a partial picture of the movement of goods across the border, as Northern Ireland relies heavily on moving and receiving goods through ports in Ireland for its trade with Great Britain.
"Previous estimates have indicated that Northern Ireland sales of goods to Great Britain are worth nearly four times that of sales of goods to Ireland of which the current exercise does not take account. North-South supply chains cannot be considered in isolation from trade with Great Britain and this remains an area for further research."
NISRA surveyed Northern Ireland businesses who trade with the Republic of Ireland and analysed HMRC trade microdata in order to provide more detailed information on the frequency and value of cross-border movements of goods and the extent of cross border supply chain linkages to inform EU Exit discussions.
Provisional estimates indicate Northern Ireland businesses - in the non-financial and non-farm sectors - made some 758,000 cross border export deliveries to the Republic. This was estimated to be worth some £3.4billion to the Northern Ireland economy in 2016.
In addition, there were approximately 410,000 import deliveries in 2015 from Ireland to Northern Ireland businesses worth nearly £2bn in the sectors covered by the survey.
The majority (74%) of the (758,000) export deliveries in 2016 were made by small businesses (with fewer than 50 employees) with a third carried out by micro businesses (with fewer than 10 employees).
Survey paints rich picture of the web of cross-border connections and trade. Department for the Economy
Much of the volume of Northern Ireland businesses’ cross-border trade was comprised of low-value trips but these accounted for just less than one fifth of the total value of exports.
In contrast just over 20% of Northern Ireland businesses who export to Ireland made deliveries to Ireland worth more than £4,500 per trip. Such businesses accounted for most (82%) of the value of Northern Ireland’s exports to Ireland (£3.4bn) in 2016.
Almost 40% of Northern Ireland trade to the Republic is comprised of "intermediate" products - that is those that are required for the production of other goods.
On a similar basis, slightly less (62%) of Northern Ireland’s trade with the Rest of the EU also showed evidence of such supply chain activity, as did 53% of Northern Ireland’s trade with the Rest of the World. However Northern Ireland’s trade with these destinations was more heavily influenced by trade in capital goods (21%, 23% of trade respectively) than Northern Ireland’s trade with Ireland (7% of such trade).