If you have solar panels and you are Googling for the best Octopus tariff, almost every answer on the open web is currently wrong. Octopus Flux and Intelligent Octopus Flux — the two tariffs that almost every solar buying guide recommends — were paused to new signups in March 2026 in response to wholesale energy market volatility. They have not reopened. This is the honest answer for May 2026, by household setup.
Why Flux is closed
Octopus Flux was designed for solar-and-battery households. It offered three rates a day — a cheap import window in the early hours (typically 02:00–05:00), a normal-priced daytime rate, and a peak-priced evening window (16:00–19:00) when grid demand is highest. The clever part was the export side: Flux paid an enhanced export rate during that evening peak, rewarding households that stored solar during the day and discharged the battery to grid at dinnertime.
The tariff worked because wholesale prices broadly behaved as expected. In late 2025 and early 2026 wholesale evening peaks became more volatile, and Octopus closed both Flux and Intelligent Flux to new signups in March 2026 while they reviewed the economics. Existing customers were not removed. As of May 2026 neither tariff has reopened. Octopus has not committed to a return date.
If you signed up to Flux before March 2026 and you are happy, do nothing. If you have moved house or want to switch suppliers, you cannot get back on it.
Best tariff by household setup
The right tariff depends on what else is in your home alongside solar. Four common setups:
| Setup | Best import tariff | Best export tariff |
|---|---|---|
| Solar only (no battery) | Octopus Tracker or standard variable | Outgoing Octopus (fixed) |
| Solar + battery | Cosy Octopus | Outgoing Octopus Fixed |
| Solar + battery + EV | Intelligent Octopus Go | Outgoing Octopus Fixed |
| Solar + battery + heat pump + EV | Intelligent Octopus Go (Oct–Mar) or Cosy (year-round) | Outgoing Octopus Fixed |
Cosy Octopus — for solar plus heat pump
Cosy gives you three cheap windows every day: 04:00–07:00, 13:00–16:00, and 22:00–00:00. During these windows electricity costs about 51% less than the peak rate, which falls in the 16:00–19:00 evening window. The shape is built around heat pumps: pre-heat the home during the early morning cheap window, top up during the afternoon dip (which often coincides with peak solar generation), avoid the dinnertime peak, then take a final cheap charge before midnight.
For a solar-and-battery home with a heat pump, this is currently the strongest combination. You charge the battery from cheap-window grid electricity when solar is short (winter mornings), discharge through the evening peak, and export the surplus from sunny days. Heat pump operation slots into the three cheap windows automatically if you have a smart thermostat.
Intelligent Octopus Go — for solar plus EV
Intelligent Octopus Go gives a single overnight cheap window from 23:30 to 05:30 — six hours at around 7p per kWh in most regions. It is significantly cheaper per kWh than Cosy’s cheap windows, but you only get one window a day. Octopus may add bonus discount slots when the grid has surplus renewable generation.
If you have an EV, this is the cheapest way to charge it at home. The six-hour window is enough to fully replenish most battery EVs from empty. If you also have a home battery, you can charge that during the same window for use the next day. Combined with solar generation during daylight, a typical four-bedroom home with solar, a 10 kWh battery and one EV can run for under £1,000 a year on this tariff.
The trade-off versus Cosy: Intelligent Go is brilliant for EV charging but worse for heat pump operation. The single overnight window does not match how a heat pump wants to run. Households with both an EV and a heat pump have to pick which device the tariff is optimised for.
Outgoing Octopus — the export side
Octopus’s standard fixed export rate is 15p per kWh under the Outgoing Octopus Fixed tariff (rate current as of May 2026). You can stack this with any of the import tariffs above. There is also Outgoing Octopus Agile, which tracks wholesale market prices and can hit 25–30p per kWh during summer evening peaks but goes negative occasionally.
For most households, the fixed 15p rate is the right choice — predictable, easy to model, and beats the Smart Export Guarantee minimum (which is 1p per kWh from most suppliers). If you have a battery and you are happy actively scheduling discharge against price signals, Agile can pay more. If you would rather not think about it, take the fixed rate.
If you have solar but no battery
This is the trickiest setup, because none of the time-of-use tariffs above are designed for you. You generate during the day, export the surplus you cannot use, and import overnight when you have no generation. There is no useful cheap window for you to shift load into.
The honest answer: take Octopus’s standard variable tariff (or Octopus Tracker if you are comfortable with daily price changes) on the import side, and Outgoing Octopus Fixed on the export side. You will not save money by switching to a time-of-use tariff unless you also add a battery to shift consumption into the cheap windows. A 5 kWh battery added to an existing 4 kW solar system typically pays back over six to eight years on Cosy.
Things to check before switching
Three points often miss:
- You need a smart meter. Every time-of-use tariff requires SMETS2 half-hourly readings. Without one you cannot sign up.
- Your meter and supplier must both support half-hourly settlement. Some older SMETS1 meters are not yet on half-hourly readings even after the firmware upgrade. Octopus will tell you if your meter is not ready.
- Your battery and EV charger need to be on the Octopus compatibility list for Intelligent control. The list is published on the Octopus website and includes most mainstream brands (Tesla, Givenergy, Solis, Ohme, Wallbox) but not all.
What you can expect to save
For a typical three-bedroom semi with 4 kW of solar, a 5 kWh battery, gas heating and one mid-size EV doing 8,000 miles a year, switching from a standard variable tariff to Intelligent Octopus Go plus Outgoing Octopus Fixed cuts a typical annual electricity bill from around £1,400 to around £750 — based on 4,500 kWh of household consumption and 3,200 miles of EV charging at home. Add an additional £350 to £450 from solar export. Real-world results vary widely with consumption habits and home layout.
Sources
- Octopus Energy smart tariffs — Octopus.energy
- Cosy Octopus explained — Sunsave
- Intelligent Octopus Go review — Sunsave
- Energy price cap unit rates — Ofgem
Frequently Asked Questions
Octopus has not committed to a return date. The pause was triggered by wholesale market volatility, so any reopening will depend on those conditions stabilising.
Yes. Outgoing Octopus is an export-only tariff that pays you for solar fed back to the grid. It runs alongside any import tariff.
Cosy Octopus is the best choice. The three daily cheap windows give your battery plenty of opportunities to charge from cheap grid electricity.
Almost always yes. The Smart Export Guarantee minimum is 1p per kWh; Outgoing Octopus Fixed pays 15p per kWh. For a 4 kW system exporting around 1,500 kWh a year, the difference is over £200 a year.
