Northern Ireland’s largest supplier of natural gas, firmus energy has written to its customers in the region to inform them of the rise.
It will come into effect from January 6, 2022.
With just over 50,000 customers, the Greater Belfast Network area covers Belfast, Lisburn, Bangor, Holywood, Donaghadee, Larne, Groomsport, Millisle, Newtownards, Carryduff, Comber, Newtownabbey, Carrickfergus, and East Down.
The move is due to the increasing cost of natural gas on the global markets, according to the company.
Gas prices previously went up by 32.98 percent from October 2021 for Greater Belfast customers, while a tariff change was also announced last month for the Ten Towns Network area.
Wholesale global gas prices have increased by 414 percent from a year ago and by 74 percent since the last tariff review.
The change in tariff will mean an extra £2.75 per week on to the average household bill.
Dr David Dobbin, Chairman of firmus energy, said: “We very much regret having to increase our Greater Belfast tariff however the sheer scale of the increases in global wholesale gas prices have forced our hand.
“We know this is an unwelcome increase which will have a disproportionate effect on those of our customers who are most vulnerable. Following ongoing discussions, we will be supporting the government and industry backed financial support scheme that is being developed to assist our most vulnerable customers this winter.
“This is not just a firmus issue, but one faced by energy suppliers across gas, oil and electricity, all of whom will have to increase their tariffs to meet the huge surge in global energy costs, if they haven’t already done so.”
The announcement means that tariffs for customers in both the Greater Belfast and Ten Towns Network areas are broadly aligned.
Customers seeking advice on their natural gas bills or direct debit payments should contact the firmus energy Customer Services team on 0330 024 9000; telephone lines are open 24 hours a day, seven days a week.
For free and independent advice on how to save energy please contact NI Energy Advice Line on 0800 111 4455.