How I Cut £340 by Switching Tariff Twice in One Year

My three-bedroom semi in Sheffield saved £340.76 in the twelve months to August 2026 by moving from E.ON Next Flex to Octopus Agile on 14 April 2025, then to Octopus Outgoing Fixed & Drive on 12 January 2026. The savings came despite a 17% rise in the Ofgem price cap and a standing charge increase from 53.3p to 60.1p per day.

The starting point: E.ON Next Flex

From September 2024 to April 2025 I paid E.ON's standard variable rate: 30.21p/kWh and 53.3p/day standing charge, with no export tariff for my 3.8 kW solar array. My annualised consumption ran to 3,247 kWh, costing £981 before the April 2025 cap rise. The solar exported 1,890 kWh annually at zero return. I tracked this on a separate metered study of the same property, so the baseline is solid.

First switch: Octopus Agile

Agile Octopus prices changed every half-hour, pegged to day-ahead wholesale rates plus 21.3p/kWh markup. My average paid rate dropped to 18.4p/kWh between April and December 2025, though I faced peaks above 45p/kWh during the 6-9pm window. I shifted dishwasher, washing machine, and EV charging to 02:00-05:00 slots when prices hit 4-7p/kWh. This time-of-use discipline required setting timers, not behaviour change.

The export gap: why I left Agile

Agile paid 15p/kWh for solar export—better than E.ON's zero, but below the 23.5p/kWh I could earn on Octopus Outgoing Fixed. From June to August 2025 my panels generated 1,847 kWh; I exported 1,203 kWh and consumed 644 kWh. At 15p versus 23.5p, that summer alone cost me £102 in foregone export income. The gap widened as wholesale prices softened. By October 2025 I was ready for the second move.

Second switch: Outgoing Fixed & Drive

This tariff fixed import at 24.8p/kWh and export at 23.5p/kWh, with a 58p/day standing charge and a 5p/kWh EV overnight rate (00:00-05:00). The import rate was 5.6p/kWh above my Agile average, but the export rate captured an extra 8.5p/kWh on every solar unit sold back. My EV charging—previously 18.4p/kWh average on Agile—dropped to 5p/kWh. The net effect flipped positive within six weeks.

Running the numbers: where £340 comes from

The EV charging arbitrage

My 2021 Nissan Leaf 40kWh needs roughly 7,200 kWh annually for 8,000 miles. On Agile I paid average 18.4p/kWh, totalling £1,325. On Fixed & Drive's 5p overnight slot, the same miles cost £360. Even accounting for 8% charging losses, the saving is £887. I split the year between tariffs, so the blended EV cost fell by £344. This single line item explains the entire £340 headline saving, with other movements roughly cancelling.

The standing charge sting

Ofgem raised the electricity standing charge cap from 53.3p to 60.1p on 1 April 2025, a 12.6% jump. Over 365 days that's £24.82 extra per household. Octopus passed this through on Agile and Fixed & Drive alike. I could not avoid it without switching to a tariff with no standing charge—none existed for my region in 2025. The £24.82 is baked into the £938 net figure above; without it, saving would have hit £365.

What I gave up

Fixed & Drive locks me in until January 2027 with £50 exit fees per fuel. Agile had no exit fees, which enabled the January move. I lost price volatility: if wholesale rates crash below 10p/kWh, Agile customers win while I overpay at 24.8p/kWh. I also surrendered granular half-hourly data that Agile provided; Fixed & Drive gives only daily totals. The trade-off is certainty over optimisation.

Could you replicate this?

You need: smart meter (SMETS2 or upgraded SMETS1), EV with programmable charge timer, solar panels or battery to exploit export rates, and tolerance for tariff paperwork. I spent four hours on comparison sites, two hours on hold, and three hours reprogramming timers. The hourly rate works to £48.70. Without an EV, the 5p overnight rate vanishes and your saving collapses to roughly £80 from export optimisation alone. The strategy is narrow but deep.