The price of natural gas is to rise by 9% from 1 April.
The Commission for Energy Regulation has announced its approval for the price rise of 9.1% for domestic and commercial customers.
The increase will mean a price rise of 11 cents per day on the average household gas bill, or €6.66 (ex VAT) on an average household bill of €73.
The increase for households will first appear on June bills.
Bord Gais had originally applied to the commission last October for a 14% increase.
The Bord later revised its application to a request for a 17% increase from 1 April.
Higher prices for gas and transportation costs have been blamed on the need for a price rise.
It is the first price rise for householders since 1984.
The CER has also published a proposal from Bord Gais for the supply of natural gas to eligible customers - those consuming more than 181,000 therms of gas per year who can choose an alternative supply of gas - on the basis of a regulated tariff formula (RTF).
Bord Gais says this formula, regulated by the CER, is designed to ensure that these customers will be offered a single, transparent market price in order to enable comparisons with quotes from other suppliers.
The RTF will result in various changes depending on the contract, but there will be an overall average rise of about 2.5%.
