Households are still being paid the €100 Water Conservation Grant, the Dáil's Public Accounts Committee (PAC) has been told.
Water charges are suspended and their future is at the centre of an ongoing row between Fine Gael and Fianna Fáil that it's feared could lead to an election.
But today TDs heard that the €100 grant payments continue to be made to householders who have an entitlement dating back to 2015.
The grant, introduced that year, offset a chunk of the cost of water charges.
John McCarthy, the secretary general of the Housing Department - which also has responsibility for water - told the PAC that water programme expenditure in 2015 included €94 for the Water Conservation Grant.
He said that as of June 20, 2015 the 1.308m households registered with Irish Water were eligible for the 2015 grant, which is administered by the Department of Social Protection.
That Department made payments totalling just over €89m to 890,104 applications by households.
Mr McCarthy added: "A small number of residual payments continue to be made to householders who have an entitlement to the 2015 Water Conservation Grant."
Water charges were suspended under the confidence and supply agreement between Fine Gael and Fianna Fáil.
A recommendation by an Expert Committee that charges should apply for wasteful or excessive use of water is currently the subject of a row between the two partys at the Oireachtas water committee.
Fianna Fail want charges scrapped outright, while Fine Gael argues that a polluter pays principle must remain in order to comply with EU law and avoid fines to the State.