She told the Seanad that Dublin residents had complained to her they were being placed in the wrong area.
“There are people all over Ireland who have been located in geographically incorrect towns, counties and even provinces,’’ said Ms White.
She claimed homes in west Wicklow had received a Kildare postcode and, according to Eircode, people in Dublin 16 actually live in Dublin 24.
“The list of inaccuracies is endless,’’ she added.
In other countries, Ms White said, codes were assigned in an orderly fashion and, as a result, areas close to each other had a similar code.
“The new Eircode system has created amazing confusion,’’ she said. “Every Government agency I have contacted about this issue has completely washed its hands of it.’’
She said even at this late stage a period of up to one year for an appeal process on anomalies should be established.
Minister of State Kathleen Lynch, standing in for Minister for Communications Alex White, said the most comprehensive database was owned by GeoDirectory, a subsidiary of An Post and Ordnance Survey Ireland and provided under licence to Eircode.
Ms Lynch said members of the public who felt their postal address was incorrect could contact An Post.
“An Post will investigate the matter and, if it decides to amend the address, it will update its central database.”