NSW households are to be hit with an average 17.8 per cent hike in gas prices from next month after a final decision on Tuesday from the Independent Pricing and Regulatory Tribunal.

The regulator's decision, which confirms a draft recommendation several weeks ago, means the typical household gas bill will jump by between $155 and $225 a year from July 1, depending on location and gas use, according to the regulator.

Gas prices in NSW are set to rise by more than 17 per cent. Credit:Glen Watson

Gas prices across eastern Australia are being driven higher by the huge jump in gas demand from LNG export projects being built in Queensland, the first of which is due to start shipments to China late this year.