The short answer
A price cap tracker gives you the Ofgem cap minus a discount, so it follows the cap straight into a forecast double-digit January rise. A fix does not. That single difference decides the tracker tariff vs fixed question this autumn.
We priced every tracker and fixed deal in our daily rate feed at Ofgem typical use, which is 2,500 kWh of electricity and 9,500 kWh of gas a year.2 The cheapest fix came out at £1,642 a year. The better of the two trackers we can price came out at £1,886 once you follow it across the next four cap windows.
Fix, and fix long. A tracker discount of £15 to £50 a year cannot offset a cap forecast to rise 16% to 21% in January, and the gap works out at roughly £210 to £245 over the next twelve months.
The two-year question is narrower than it looks. The cheapest 24-month deal we price is £131 a year dearer than the cheapest 18-month one, and the extra lock only pays off if energy costs more than £2,166 a year from April 2028.
Every tracker and fixed deal, priced
The cap for October to December 2026 is £1,723 a year at typical use, built from a 26.32p unit rate and a 54.83p daily standing charge on electricity, plus 7.97p and 29.68p on gas.1 Every figure below uses the same meter readings, so the ranking is like for like rather than a list of marketing claims.
| Tariff | Type | Cost a year | Versus the cap | Exit fee |
|---|---|---|---|---|
| Fuse Energy Fixed 18m | Fixed, 18 months | £1,689 | -£30 | £50 per fuel |
| EDF Simply Tracker | Price cap tracker | £1,672 | -£50 | £100 |
| Scottish Power Cap Tracker | Price cap tracker | £1,706 | -£15 | £50 |
| Ofgem cap (default tariff) | Variable | £1,723 | — | None |
| So Energy Kookaburra Loyal 24m | Fixed, 24 months | £1,750 | +£23 | £90 per fuel |
| So Energy Kookaburra 24m | Fixed, 24 months | £1,773 | +£46 | £90 per fuel |
| So Energy Kookaburra 18m | Fixed, 18 months | £1,854 | +£126 | £90 per fuel |
| So Energy Kookaburra 12m | Fixed, 12 months | £1,891 | +£170 | £71 per fuel |
Two things stand out. Long fixes undercut short ones, which is the reverse of the usual pattern: at So Energy the 24-month deal prices more than £100 a year below the 12-month one. And the better tracker sits within £30 of the cheapest fix today, so the two look close until the cap moves.
Wider market lists put a Fuse Energy 24-month fix at 4.8% below the cap.3 It is not in our feed today, so the 18-month Fuse fix above is the cheapest price we can stand behind. Our Fuse Energy review covers what you give up on service to get it.
Where a tracker discount actually comes from
Every price cap tracker advertises one number. Rate-level data shows two trackers can advertise the same discount and behave nothing alike, because a discount can land on unit rates or on the standing charge.
Both trackers we can price discount the standing charge and leave unit rates alone. EDF Simply Tracker takes £50 a year off standing charges and charges the cap unit rate to the penny. Scottish Power Cap Tracker does the same for £15. Neither touches the half of the bill that is about to move.
| Tariff | Off unit rates | Off standing charges | What that means when the cap rises |
|---|---|---|---|
| EDF Simply Tracker | £0 | £50 | The discount stays at £50 however high the cap goes, because standing charges barely move. |
| Scottish Power Cap Tracker | £0 | £15 | The discount stays at £15, which is close enough to the cap to be a rounding error. |
| Fuse Energy Fixed 18m | -£6 | £95 | The price is locked, so the gap against the cap widens by itself every time the cap rises. |
That decides how a tracker behaves this winter. Cornwall Insight's January forecast of £1,999 puts almost the whole rise on unit rates, leaving the daily standing charge near where it is.4 A unit-rate discount grows with the cap. A standing-charge discount holds at £50 or £15 while the bill it comes off climbs.
Market lists do carry unit-rate trackers, led by Outfox at 7% off unit rates.3 None is in our feed today, so we cannot verify a price. On the same forecast path a 7% discount would land near £1,822 a year, still well above the cheapest fix.
Britain's biggest generator of zero-carbon electricity
EDF runs the UK nuclear fleet alongside wind and solar, and powers around one in five British homes. Simply Tracker is its cap-linked option in the table above, and its fixed deals sit on the same page if you would rather lock a price in.
See EDF tariffs →*Affiliate disclosure - the EDF link above is an affiliate link. SwitchInsights earns a commission when readers switch through it, at no extra cost to you. That commission has no influence on what we write. EDF Simply Tracker places second in the table above on our own numbers, behind a fix we earn nothing from, and we say so.
Year one: the January price cap decides it
Cornwall Insight forecasts the cap at £1,999 in January, a rise of £276 or 16% and the largest since January 2023.4 The supplier forecasts compiled by MoneySavingExpert run higher at £2,085, then £2,061 in April and £1,876 in July, averaging £1,936 across the four windows.3 That £1,936 is a twelve-month average of four forecast caps, priced on the same Ofgem typical use as today's £1,723, so it is the path ahead and not a restatement of the cap in force now. It is also not the £1,935 some sources still quote for this quarter, which is today's cap restated on the higher pre-2026 consumption benchmark. Every tracker rides that path, minus its discount. Every fix ignores it.
The cheapest fix comes in £245 a year below the better tracker and £295 below the default tariff. On Cornwall Insight's lower path the gap narrows to £208, which changes the size of the answer and not the answer itself.
That gap is not a forecasting call. The fix is already £84 below today's confirmed cap, before any rise lands, so a tracker needs prices to fall below where they are now just to draw level.
Is a 2 year fixed energy deal worth it?
Fixing long is cheap right now, which is unusual. The question is how long. Our feed prices the cheapest 18-month fix at £1,642 and the cheapest 24-month fix at £1,773, a difference of £131 a year for six extra months of certainty.
Over the same 24-month window the trade is clear. The 18-month deal covers 18 months at £1,642, then leaves six exposed to whatever is on offer from April 2028. The 24-month deal covers all 24 at £1,773.
| Option | First 18 months | Final 6 months | Two-year total |
|---|---|---|---|
| 18-month fix, then re-fix at £1,700 | £2,462 | £850 | £3,312 |
| 18-month fix, then re-fix at £2,166 | £2,462 | £1,083 | £3,546 |
| 18-month fix, then re-fix at £2,500 | £2,462 | £1,250 | £3,712 |
| 24-month fix at £1,773 | £2,660 | £886 | £3,546 |
The 24-month lock only wins if energy costs more than £2,166 a year from April 2028, above the peak of every January 2027 forecast here. Forecasters expect prices to ease through 2027 instead. On today's prices the shorter fix is the better buy.
The break-even figure is arithmetic on two scraped prices, so it moves if either changes. Three things shift it:
- A cheaper 24-month deal. Market lists show a Fuse 24-month fix at 4.8% below the cap, which is around £1,640. At that price the two terms cost almost the same and the longer lock becomes the obvious pick, so it is worth checking whether it is available for your postcode.
- Electricity VAT. Electricity is zero-rated until 31 March 2027. If that ends, every tariff above rises together, so the ranking holds and the totals do not.
- Exit fees. Leaving the 18-month fix early costs £50 per fuel, so £100 on dual fuel. That is the cost of changing your mind, and it is lower than on any 24-month deal we price.
Flexibility is the main pitch for a price cap tracker, and most charge to use it. Our feed records £50 on Scottish Power Cap Tracker and £100 on EDF Simply Tracker.
Read the fee against the discount. A tracker £15 a year below the cap with a £50 exit fee takes over three years to earn back the cost of leaving.
Which energy deal suits you
- Most households: the cheapest long fix. An 18-month fix at £1,642 covers the whole forecast cap peak and costs £84 less than the cap before any rise lands.
- Certainty to late 2028: a 24-month fix, but a cheap one. Pay no more than about £40 a year over the best 18-month price, or the extra six months are not worth it.
- Expecting a fast fall in prices: a unit-rate tracker. Take the discount that grows with the cap, and check the exit fee first.
- Still on a default tariff: move either way. Sitting on the cap is the single most expensive option in the table, at £1,936 over the next twelve months on the forecast path against £1,723 at today's rates.
Compare live prices for your own postcode on the SwitchPilot tariff tracker, and read our breakdown of the confirmed October cap for what is driving the January rise. This article is not financial advice.
How SwitchInsights put this guide together: we price every tariff from our own daily rate feed, which scrapes each supplier's published unit rates and standing charges across the 14 UK regions, costs them at Ofgem typical use and takes the median. We measure each tracker against its own regional cap rate, not the national headline, which is what separates a unit-rate discount from a standing-charge one. Forecast caps are third-party figures, named where we use them, and every cap figure here carries its basis: which consumption benchmark it uses and whether it is one quarter or an average of several. Where a supplier blocks our scraper or a tariff leaves the feed, we say so rather than fill the gap with a number we cannot stand behind.