Should I Switch to a Gas-Only Tariff? UK Decision Guide 2026
With the July 2026 cap pushing gas bills up ~24%, single-fuel deals deserve a fresh look. Here is when they win, when they do not, and exactly how to decide.
What is a gas-only tariff?
A gas-only tariff supplies just your gas through one energy account, leaving electricity to a separate provider. Most households in the UK take a dual-fuel deal, meaning one supplier covers both fuels, but the market has always allowed you to split them. Some suppliers, including Octopus Energy, E.ON Next and British Gas, offer single-fuel contracts for either fuel independently.
Splitting fuels means two direct debits, two sets of standing charges, and two customer-service relationships. The potential upside is access to a lower unit rate on gas from a specialist deal, or the ability to fix one fuel without the other when the two markets are moving differently.
When a gas-only tariff can save you money
Gas-only can win when...
- You already have a locked-in electricity fix and only need to sort your gas.
- A supplier offers a gas-only rate materially below the cap and no equivalent dual-fuel deal.
- Your electricity comes via a heat pump or EV-optimised tariff (e.g. Octopus Cosy, Go) that cannot be bundled.
- You are a landlord managing multiple meters across different addresses.
- You consume a high volume of gas (well above the 11,500 kWh/yr typical) so even a small unit-rate saving adds up significantly.
Dual fuel stays better when...
- Your supplier offers a dual-fuel discount (typically £20-£50/yr) that offsets any unit-rate difference.
- You want one bill, one direct debit and one customer-service line.
- The best gas-only rate available is within 0.3p/kWh of the best dual-fuel gas rate.
- You prefer simplicity over optimisation and switch energy less than once a year.
- Your electricity usage is high, so splitting and losing a bundled electricity fix would cost more than you gain on gas.
Worked cost comparison (typical home, July 2026 cap rates)
A typical UK home uses around 11,500 kWh of gas per year. The table below compares three scenarios at July 2026 rates.
| Scenario | Gas unit rate | Gas standing charge | Annual gas cost | Dual-fuel discount | Net annual gas cost |
|---|---|---|---|---|---|
| Cap dual-fuel gas portion (July 2026) | 7.33p/kWh | 29.04p/day | ~£948 | -£30 (illustrative) | ~£918 |
| E.ON Next Fixed gas-only (illustr. ~£1,602/yr total) | ~7.10p/kWh | ~28p/day | ~£920 | None (single fuel) | ~£920 |
| Octopus 12M Fixed dual-fuel (illustr. ~£1,632/yr total) | ~7.15p/kWh | ~28.5p/day | ~£927 | -£25 (illustrative) | ~£902 |
Illustrative rates based on publicly available market data as at June 2026. Your actual costs depend on usage, region and supplier. Always compare your own usage before switching.
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How the July 2026 cap changes the maths
From 1 July 2026 the Ofgem cap rose to £1,862/yr for a typical dual-fuel household paying by direct debit, up from £1,641/yr this quarter (an increase of £221, or roughly 13%). But the rise is not equal across fuels:
- Gas bills up ~24%: the gas unit rate climbs to 7.33p/kWh and the daily gas standing charge becomes 29.04p/day.
- Electricity bills up ~5%: the electricity unit rate rises to 26.11p/kWh with a daily standing charge of 57.19p/day.
This asymmetry matters for the gas-only decision. Because gas is bearing most of the cap rise, the potential saving from locking in a gas fix now is larger than usual. A household that fixes gas at a rate 0.5p/kWh below the July cap saves roughly £57/yr on a 11,500 kWh annual gas bill. Against a dual-fuel discount of £25-£30, that creates a genuine net saving on gas alone, before even considering the electricity side.
However, roughly 22 million UK accounts (around 40% of the market) are already on fixed deals and will not see the July increase at all. If you are one of them, the urgency around gas-only switching is much lower. Check your current deal expiry date first.
Also note that with the July cap confirmed, several suppliers have launched dual-fuel fixes at or below £1,862/yr, including E.ON Next at an illustrative ~£1,602/yr and Octopus 12M Fixed at ~£1,632/yr. These dual-fuel fixes are worth comparing against any gas-only deal because they lock in both fuels and preserve any bundled discount.
How to switch to a gas-only tariff in five steps
- Find your current deal and expiry date. Log into your supplier account or check your bill. Note whether you are on a variable cap rate or a fixed deal. If you are mid-fix, check any early-exit fees (typically £25-£75 per fuel).
- Compare gas-only deals. Use a comparison tool that lets you filter by single fuel. Enter your annual gas usage in kWh (or your typical monthly spend) and your postcode to get region-accurate rates. Check both the unit rate and the daily standing charge.
- Factor in the dual-fuel discount you will lose. Ask your current supplier what dual-fuel discount they apply. Subtract this from any apparent saving on a gas-only deal. If the net saving is under £15/yr, convenience of dual fuel likely wins.
- Initiate the switch. Switches typically complete within five working days under the Switch Guarantee. You have a 14-day cooling-off period after signing. You do not need to contact your old supplier; the new one handles the handover.
- Arrange your electricity separately if needed. If you are leaving a dual-fuel deal, either confirm your electricity stays with the old supplier (you may move to their standard variable rate) or switch electricity simultaneously to avoid being left on a poor rate.
Frequently asked questions
Can I get a gas-only tariff from any supplier?
Not all suppliers offer single-fuel contracts. Octopus Energy, E.ON Next, British Gas, EDF, OVO and Utility Warehouse all offer gas-only options as at June 2026, but availability and rates vary by region. Always run a comparison with your postcode to see what is actually available at your address.
Will I pay two standing charges if I split suppliers?
Yes. Splitting gas and electricity means two daily standing charges. From 1 July 2026 the cap rates are 29.04p/day for gas and 57.19p/day for electricity, totalling roughly £315/yr in standing charges alone. On a dual-fuel deal you still pay both standing charges, so this is not extra cost from splitting, but it is worth confirming both rates when comparing.
How much is the dual-fuel discount and is it worth it?
Dual-fuel discounts vary by supplier and deal, but typically range from £20 to £50 per year as at June 2026. On a high-gas-usage home where a gas-only fix saves £60-£80/yr versus the cap, the net gain after losing the discount can be worthwhile. On a typical home the margin is thin enough that the convenience of one supplier often tips the decision toward dual fuel.
Does the July 2026 cap make switching more urgent?
The July 2026 cap rise (announced 27 May 2026) takes gas to 7.33p/kWh from 1 July. If you are currently on the variable cap, your gas bill rises ~24% from that date. Fixed deals available now lock in rates below the July cap level, so switching now can save money on both gas-only and dual-fuel deals. Five working days is the typical switch time, so acting in mid-June gives enough lead time.
What if I am already on a fixed deal?
Around 40% of UK energy accounts (approximately 22 million) are on fixed deals and will not be affected by the July 2026 cap rise. If your fix expires before September 2026, now is a good time to compare what replaces it. If your fix runs into 2027 or later, you may want to hold unless an early-exit penalty is waived and a materially better deal is available.
How long does a gas-only switch take?
Under the Energy Switch Guarantee, switches complete within five working days for direct debit customers. You have a 14-day cooling-off period after agreeing a new deal, during which you can cancel without penalty. Your supply is never interrupted during a switch.
Which suppliers are safe to switch to right now?
As at June 2026, reputable suppliers to consider include Octopus Energy, E.ON Next, EDF, OVO Energy, British Gas, Utility Warehouse, and Good Energy. GivEnergy entered administration in April 2026 and should not be considered. Always check a supplier is Ofgem-licensed and review recent customer service scores before committing.
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