SIPTU says it wont accept any unilateral changes to the terms of employment of their members at Irish Water.
It comes after the Government announced that it was freezing bonuses at the utility pending a review.
A spokesperson for parent company Ervia confirmed that no payments will be made for either 2013 or 2014 until the independent review is completed.
However, SIPTU says the payment system in operation in Irish Water is a performance-based pay system introduced in 2012 in Bord Gais.
The union says it will not accept that SIPTU's "modestly paid members" should have their terms of employment cancelled without agreement.