Is a home battery worth it on Flexible Octopus?

Flexible Octopus is the standard variable tariff: one price all day, moving with the Ofgem price cap. With one price there is nothing for a battery to shift between, so a battery on Flexible only helps if it stores surplus solar.

The tariff in brief

Price patternOne price all day.
Who can get itAnyone. Octopus’s standard variable tariff, tracking the Ofgem price cap.
Octopus product codeVAR-22-11-01
London unit rates27.9p per kWh
London standing charge43.5p per day

Octopus public API, fetched 25 October 2026. Import prices shown with the normal 5% VAT (VAT is off bills from 1 October 2026 to 31 March 2027).

A day on this tariff in London

00:00 27.9p 00:30 27.9p 01:00 27.9p 01:30 27.9p 02:00 27.9p 02:30 27.9p 03:00 27.9p 03:30 27.9p 04:00 27.9p 04:30 27.9p 05:00 27.9p 05:30 27.9p 06:00 27.9p 06:30 27.9p 07:00 27.9p 07:30 27.9p 08:00 27.9p 08:30 27.9p 09:00 27.9p 09:30 27.9p 10:00 27.9p 10:30 27.9p 11:00 27.9p 11:30 27.9p 12:00 27.9p 12:30 27.9p 13:00 27.9p 13:30 27.9p 14:00 27.9p 14:30 27.9p 15:00 27.9p 15:30 27.9p 16:00 27.9p 16:30 27.9p 17:00 27.9p 17:30 27.9p 18:00 27.9p 18:30 27.9p 19:00 27.9p 19:30 27.9p 20:00 27.9p 20:30 27.9p 21:00 27.9p 21:30 27.9p 22:00 27.9p 22:30 27.9p 23:00 27.9p 23:30 27.9p 00:0006:0012:0018:00
Unit rate for each half-hour, London
All 48 half-hours
Timep/kWhTimep/kWh
00:00 27.9p 12:00 27.9p
00:30 27.9p 12:30 27.9p
01:00 27.9p 13:00 27.9p
01:30 27.9p 13:30 27.9p
02:00 27.9p 14:00 27.9p
02:30 27.9p 14:30 27.9p
03:00 27.9p 15:00 27.9p
03:30 27.9p 15:30 27.9p
04:00 27.9p 16:00 27.9p
04:30 27.9p 16:30 27.9p
05:00 27.9p 17:00 27.9p
05:30 27.9p 17:30 27.9p
06:00 27.9p 18:00 27.9p
06:30 27.9p 18:30 27.9p
07:00 27.9p 19:00 27.9p
07:30 27.9p 19:30 27.9p
08:00 27.9p 20:00 27.9p
08:30 27.9p 20:30 27.9p
09:00 27.9p 21:00 27.9p
09:30 27.9p 21:30 27.9p
10:00 27.9p 22:00 27.9p
10:30 27.9p 22:30 27.9p
11:00 27.9p 23:00 27.9p
11:30 27.9p 23:30 27.9p

That makes Flexible the baseline: if you are on it now, the first saving usually comes from switching to a tariff with cheap hours — with or without a battery.

What a battery saves on Flexible Octopus: four modelled homes

London prices, typical-household profiles (Elexon Profile Class 1 shape), battery 95% usable, 90% round trip. “Most to pay” is the 10-year price ceiling with capacity fading to 80%.

Home Bill, no battery 5 kWh saves 10 kWh saves 13.5 kWh saves Most to pay for 10 kWh
Typical home, 2,500 kWh a year £857 £0£0£0 £0
Home all day, 3,500 kWh £1,136 £0£0£0 £0
Electric car, 2,700 + 2,000 kWh £1,471 £0£0£0 £0
Heat pump, 2,700 + 3,500 kWh £1,890 £0£0£0 £0

For comparison, the typical home pays £857 a year on Flexible Octopus without a battery; Flexible Octopus in London is 27.9p per kWh.

Run Flexible Octopus on your own meter data

Flexible Octopus in every region

Region Standing charge, p/day Unit rate
A Eastern England 53.07 27.9p
B East Midlands 52.71 26.6p
C London 43.46 27.9p
D Merseyside and North Wales 70.63 29.3p
E West Midlands 59.08 26.9p
F North East England 63.84 26.7p
G North West England 46.42 27.8p
H Southern England 48.62 27.8p
J South East England 53.60 28.2p
K South Wales 57.17 27.9p
L South West England 57.22 27.9p
M Yorkshire 63.93 26.9p
N South and Central Scotland 63.72 27.4p
P North Scotland 56.86 27.7p

Frequently asked questions

Is a home battery worth it on Flexible Octopus?

Not on its own. Flexible Octopus charges the same price all day, so a battery has nothing to shift; in Fortyeight’s model it saves nothing for a home without solar. Switch to a time-of-use tariff first.

Who can get Flexible Octopus?

Anyone. Octopus’s standard variable tariff, tracking the Ofgem price cap.

What are the cheap hours on Flexible Octopus?

One price all day. Times are UK clock time, as published by Octopus in October 2026.

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