There has been a 13-and-a-half percent rise in the number of households who are behind on their electricity bills in just three months.
It has led to calls for the Government to put more pressure on energy companies to bring consumer prices down.
New figures from the energy regulator, the CRU, found over 400 thousand households in arrears in either gas or electricity in May.
In February, nearly 212 thousand households were behind on electricity - which rose to over 240 thousand by the end of May.
There was an eight percent rise in those in arrears in their gas bills in the same period to 165 thousand.
In the Dáil yesterday, Tánaiste Micheál Martin called on energy companies to reflect on the substantial drop in wholesale electricity prices.
Separately, CRU also said 137 households had their electricity cut off and 196 had their gas cut off for non-payment reasons in May.
