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Why Choose Us?

Here are just some of the things that make us different and a few reasons why we think you should trust firmus energy to supply your energy needs:

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Why firmus energy?

We are the natural gas people. firmus energy provides safe, cheaper, practical and environmentally-friendly natural gas to homes and businesses in Northern Ireland.

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Local base, World scale

firmus energy is part of iCON Infrastructure that has significant experience in owning and managing core infrastructure businesses, including regulated utilities in the United Kingdom and overseas.

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Protecting Northern Ireland’s environment

We love protecting Northern Ireland’s environment. firmus energy natural gas has displaced about 650,000 tons in carbon emissions (CO2) . In lay man’s terms that’s like taking 22,000 cars off the road.

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Building the firmus energy network

We have been building out our natural gas network since 2006 and in that time have laid approximately 1000km of gas mains to bring a safe, affordable home heating alternative. That’s like travelling from our Antrim office to the Eiffel Tower. C'est une longue distance!

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We take responsibility

At firmus we regularly test ourselves to make sure we are leading by example with our ethics and values. CORE, an accredited corporate responsibility accolade is our 'prefect' badge for doing good business. 

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Switch to firmus energy

Come join us - we know you would like it here. You can switch to cheaper natural gas now by clicking on the big Orange button, or if you still need to chat to our 1st class customer service team then call us on our Freephone number 0800 0324 567. 

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What kind of business are you?

Why am I having to do this?

To give you the most accurate information for your town and county, please enter your postcode below.

How do you pay for your natural gas?

By Credit

Do you receive a monthly bill for your energy usage?


With a Pay as You Go card

Do you purchase a top-up card for your energy?


What kind of business are you?

Small or Medium Business

Small businesses spend about £2,600 or less per bill. Medium businesses spend about £35,000 or less per bill.


Large Business

Large businesses spend about £250,000 or less per bill

Make sure you have your bank details and SMP number ready

Bank details

All we need is your account number and sort code *


SMP Number

This is the number usually at the top right of your bill

Okay, I have them

If your account requires 2 signatures, or you are not the bank account holder, please call us first on 0800 032 4567
If you don’t have this number, call our switch team on 0800 032 4567