If your home uses both electricity and gas, you have a choice most people never think about: take both from the same supplier on a dual-fuel bundle, or shop around for the cheapest electricity deal and the cheapest gas deal independently.
Energy suppliers want you to bundle. They offer dual-fuel discounts precisely because a customer who moves both fuels is worth more to them — and less likely to switch away for one. But a discount on a more expensive plan can still work out worse than two separately chosen best-in-market rates. Here's how to think about it.
What Is a Dual Fuel Plan?
A dual fuel plan means a single supplier bills you for both your electricity and your natural gas. In Ireland, the main suppliers offering dual-fuel packages are Bord Gáis Energy, SSE Airtricity, Energia, and Electric Ireland.
The incentive is a dual-fuel discount — typically an additional 5–10% off one or both fuels when you take the pair together. Some suppliers frame it as a higher percentage off the combined bill; others apply the bonus discount to just one fuel. Read the offer carefully.
The Case for Bundling
Dual-fuel bundles make the most sense when:
- One supplier genuinely leads on both fuels. If a supplier has the cheapest electricity tariff AND the cheapest gas tariff, bundling gives you the dual-fuel discount on top — a clear win.
- You value simplicity. One bill, one direct debit, one customer service number. For households that find energy admin stressful, this has real value.
- The dual-fuel discount is significant. A 10% additional discount on gas for a 11,000 kWh household is worth roughly €100–€150 per year. That is meaningful.
The Case for Keeping Them Separate
Separate plans make the most sense when:
- Different suppliers lead on each fuel. It is common for the cheapest electricity tariff and the cheapest gas tariff to come from different companies. If one supplier undercuts the field on electricity while another is cheapest on gas, you save more by splitting them — even after losing the dual-fuel bonus.
- Your discount expiry dates are out of sync. If your electricity discount expires six months before your gas discount, switching gas too early costs you. Independent plans let you switch each at the optimal time.
- You want maximum flexibility. With separate plans, if your electricity supplier raises prices, you can switch just that fuel without touching your gas contract.
Running the Numbers: An Example
Consider a household using 4,200 kWh of electricity and 11,000 kWh of gas per year.
Option A — Dual Fuel Bundle (Supplier X)
- Electricity: €1,150/year
- Gas: €1,100/year
- Dual fuel discount: 8% off gas = −€88
- Total: €2,162/year
Option B — Separate Best-in-Market
- Electricity from cheapest supplier: €1,050/year
- Gas from cheapest gas supplier: €1,030/year
- No dual-fuel discount
- Total: €2,080/year
In this example, the separate approach saves €82/year despite giving up the dual-fuel discount. The maths shifts if the dual-fuel supplier also leads on both individual tariffs — which is why you need to run the comparison both ways.
How to Work It Out
- Go to GoSwitch and compare electricity tariffs. Note the cheapest annual cost for your kWh.
- Switch to Gas and compare gas tariffs. Note the cheapest annual cost for your gas kWh.
- Add the two together. That is your best-case separate-plans annual total.
- Find the best dual-fuel offer. Check Bord Gáis Energy and SSE Airtricity dual-fuel pages directly, or filter for your main supplier on GoSwitch.
- Compare the totals. Whichever is lower, go with that.
Which Suppliers Offer Dual Fuel Bundles in Ireland?
| Supplier | Dual Fuel Available? | |----------|---------------------| | Bord Gáis Energy | ✅ Yes — electricity + gas bundle | | SSE Airtricity | ✅ Yes — electricity + gas bundle | | Energia | ✅ Yes — electricity + gas bundle | | Electric Ireland | ✅ Yes — electricity + gas bundle | | Pinergy | ❌ Electricity only | | Flogas | ❌ Gas only (residential) | | Community Power | ❌ Electricity only |
The Verdict
There is no universal answer. The right choice depends on who is cheapest on each fuel at the time you are switching — and that changes regularly as suppliers adjust their tariffs and promotional offers.
The one thing that is always true: do not assume bundling is cheaper just because there is a dual-fuel discount. Run the numbers. A 7% dual-fuel discount applied to an already-expensive plan often loses to two separately chosen best-in-market rates.
Use GoSwitch to compare electricity and compare gas independently, add the totals, then stack that against whatever dual-fuel bundle you have been quoted. The answer will be clear.