The Irish Council for Civil Liberties has lodged a complaint with the Data Protection Commission relating to GeoDirectory, the location address data service established by An Post and Ordnance Survey Ireland.
The ICCL claims GeoDirectory is selling personal information, such as social class and family status, to companies.
The ICCL says it was able to buy data about people living in Limerick and Dublin and whether they are "deprived", "struggling" or "affluent".
"I was able to buy data about each of my neighbours, how much money they have and whether they are single or not. This information is specially protected under EU law," said ICCL's Tech and Human Rights Officer Olga Cronin.
The ICCL says 2.2 million Irish homes and their residents are profiled under headings such as "striving urban singles", "deprived urban families" or "struggling older families".
The ICCL claims that GeoDirectory is in breach of the General Data Protection Regulation (GDPR) because EU data protection law defines any information that can single out a person "directly or indirectly" as protected personal data.
GeoDirectory was jointly established by An Post and Ordnance Survey Ireland to create and manage Ireland's only complete database of commercial and residential buildings.
The database is used by many different companies and organisations such as the Central Statistics Office, local authorities, utility companies, banks and insurance providers.
In a statement, GeoDirectory said it uses only publicly available information.
"We are unaware of any complaint to the Data Protection Commissioner, but happy to engage with the Commissioner if required," it added.
The Central Statistics Office has said it never sells or shares information with third parties and that all information provided to the CSO is fully confidential and protected by law.
"All data published by the CSO is in aggregate form so that it never identifies individuals or households," the body said in a statement.
"No details related to an identifiable person or individual household are ever divulged to private businesses, government departments or public bodies," the CSO said.