Fewer than 20 per cent of transactions in rural areas are being carried out in euro, according to an RGDATA survey.
Ms Ailish Forde, director general of RGDATA, blamed the low use of the new currency on the reduction of banking services in isolated areas.
"We even have one member in the west who confirmed that no euro currency had yet been tendered by a consumer by day four of the currency," she said.
Ms Forde said the results of the survey of RGDATA members highlighted a "definite urban and rural divide" in the use of euro by consumers.
She said there was widespread use of the new currency in urban areas where customers had access to banks and ATM machines - as high as 90 per cent in the Dublin area.
The head of the Euro Changeover Board of Ireland, Mr Philip Hamell, said the result of the survey was "not unexpected".
Mr Hamell said he remained confident that the majority of transactions would be in euro by the end of the weekend.
