What is Octopus Agile? Half-Hourly Electricity Pricing Explained
Most electricity tariffs charge a single flat rate per kWh, regardless of when you use it. Octopus Agile works differently — the price changes every 30 minutes, tracking the wholesale electricity market. Use power when it's cheap and you can cut your bills substantially. Use it at peak times and you'll pay more.
How the pricing works
Electricity wholesale prices are traded on the day-ahead market, meaning tomorrow's prices are set today. Octopus pulls those prices and passes them directly to Agile customers — plus their margin — resulting in a different unit rate for each 30-minute slot across the day.
Prices are typically published by around 4pm each day, covering the following 24 hours in half-hour blocks from midnight to midnight. This gives you time to plan when to run your appliances.
Prices vary by region. England, Wales, and Scotland are split into 14 DNO (Distribution Network Operator) areas, each with slightly different rates based on local grid conditions and costs. That's why ElectricityNow lets you select your region — prices in London differ from prices in Yorkshire or South Scotland.
What drives the price up and down?
Several factors influence where half-hourly prices land on any given day:
- Renewable generation — when wind and solar output is high, wholesale prices fall. Overnight and on breezy days you'll often see prices drop to 3–5p/kWh or lower.
- Demand — the morning peak (7–9am) and evening peak (5–7pm) push prices up as millions of households and businesses draw from the grid simultaneously.
- Gas prices — gas plants still provide a significant share of UK electricity generation, so gas market movements feed directly into electricity costs.
- Negative prices — on days with very high renewable output and low demand (often weekend nights or very windy periods), wholesale prices can go negative. Octopus passes these through, meaning Agile customers can literally be paid to use electricity during those windows.
Who is Octopus Agile best suited to?
Agile rewards flexibility. The more you can shift your usage away from peak hours and towards cheap windows, the more you save. It works particularly well for:
EV owners — charging overnight, when prices are typically at their lowest, can cost a fraction of daytime rates. On a 7.4kW home charger, timing a full charge to a cheap window versus peak hours can save several pounds per session.
Households with flexible routines — if you can run the washing machine, dishwasher, or tumble dryer outside of peak hours, those savings compound quickly across a year. Use the savings calculator on the homepage to see what shifting one appliance could save you annually.
Smart home users — smart plugs and home automation systems can be scheduled to trigger appliances during cheap slots automatically, removing the need to track prices manually.
People with home batteries or solar — Agile pairs well with battery storage. You can charge your battery at cheap (or negative) rates and discharge during expensive periods.
Who should think carefully before switching
Agile isn't for everyone. If your household uses most of its electricity in the morning and evening — the classic commuter pattern — you could end up paying more than on a standard tariff, because those are reliably the most expensive windows.
Similarly, if you're not able or willing to monitor prices and shift usage, the variable nature of Agile removes the benefit. The tariff rewards active engagement; passive usage doesn't save money on its own.
It's also worth noting that the price cap that applies to standard variable tariffs doesn't apply to Agile in the same way — prices can spike significantly during cold snaps or grid stress events, though Octopus does apply a cap of 100p/kWh per slot.
Tips for making the most of Agile
Check prices the evening before. Agile prices are published by around 4pm. A quick glance tells you whether tomorrow morning or evening is expensive, and lets you plan accordingly.
Focus on your biggest appliances. The kettle uses barely anything per cycle. The tumble dryer, EV charger, and immersion heater are where timing actually matters. See typical usage figures in the appliance library.
Don't obsess over every slot. The biggest wins come from avoiding the peak windows (roughly 4–7pm on weekdays) and catching the genuinely cheap overnight slots. You don't need to optimise every single cycle.
Use the carbon intensity signal too. Cheap slots often (though not always) correlate with high renewable generation, meaning shifting usage to those windows is better for the environment as well as your wallet.
How to track live Agile prices
ElectricityNow shows live Octopus Agile unit rates for your region, updated in real time. The homepage tells you the current price, the cheapest upcoming windows today, and the peak slot to avoid — along with a calculator showing exactly how much you'd save by shifting specific appliances to the cheapest time.