Electric Ireland customers will see their bills increase as the company announced that its electricity prices will increase by 5.9% and gas prices by 8.5% from 1 October of this year.
It has 1.3 million electricity customers of whom 60,000 are gas customers as well.
In a statement, the company said this will result in an average increase of €1.22 per week on the average residential electricity bill.
It blames the increase on the rise in transmission and distribution network costs and the Public Service Obligation levy which it says accounts for two thirds of the overall increase.
The remainder, it says, is due to the impact of the weak euro on its wholesale energy costs.
This follows this week's announcement from Bord Gáis that its gas prices are going up for its 400,000 customers.
Airtricity has said its gas prices will increase in the near future.
Flogas has said it is reviewing its prices.