The daily pricing cycle: what happens at 4pm
Every afternoon at around 4pm, Octopus Energy publishes the next day's Agile prices. All 48 of them, covering every half-hour from midnight to midnight of the following calendar day.
The 4pm publication is not arbitrary. It follows from the structure of the wholesale electricity market. The EPEX Spot day-ahead auction closes around midday. Market clearing and settlement takes a few hours. By early afternoon, wholesale prices for every half-hour of tomorrow are confirmed. Octopus applies regional distribution charges, levies, and VAT, then pushes the complete price set to its systems by approximately 4pm.
Some days the prices land a little earlier, around 3:30pm. Occasionally they are slightly delayed to 4:30pm or 5pm if there are settlement or data issues. But 4pm is the expected window. If you build a habit of checking the dashboard in the late afternoon, you'll rarely miss the publication.
The window between 4pm and bedtime is the most valuable window in your Agile routine. That's when you have the full overnight picture in front of you and can make decisions that will shape your bill for the next 16 hours. Check the AgileAlert dashboard after 4pm each day and the cheap windows for your region will be right there, clearly charted.
Where to find tomorrow's prices
There are three places to access Agile prices once they're published.
AgileAlert. The live dashboard shows half-hourly prices for all 14 UK regions on a single page. Select your region, read the chart, identify the overnight cheap windows and any plunge events. No account required. Updated continuously. This is the fastest way to see the full picture for your region.
The Octopus Energy app. If you're an Octopus customer, your app includes a price chart showing current and upcoming Agile rates for your account region. It's well-designed and easy to read. The limitation is that it shows your region only, and doesn't offer comparison across regions or alerts for plunge events.
The Octopus public API. Octopus makes its price data available via a free public API. Home automation users, particularly those running Home Assistant with Octopus energy integrations, can query this directly and trigger smart plugs, heating, EV chargers, and other devices automatically based on live prices. This is the most powerful option for technically minded customers who want full automation rather than manual timer-setting.
For most households, the AgileAlert dashboard covers everything you need. Open it after 4pm, note where the cheap windows are, and set your timers. The whole process takes two minutes.
How to read the price chart
The Agile price chart looks like a bar chart with 48 bars, one for each half-hour of the day. The height of each bar represents the unit rate in pence per kilowatt hour.
Reading it correctly takes moments once you know what to look for.
Find the overnight valley. Look for the lowest bars, typically clustered between 11pm and 6am. This is your primary cheap window. On most days it sits between 2-8p/kWh. On high-wind nights it can dip lower.
Identify the evening peak. The tallest bars usually appear between 4pm and 8pm. These are the slots to avoid with large appliances. On a normal day they sit at 20-35p. On a cold, calm day they can reach 40-50p or more.
Look for negative bars. Any bar dropping below zero is a plunge event. These are the most valuable slots of all. Every unit you consume during a plunge earns you a credit on your account.
Note the mid-day profile. The slots between 7am and 4pm are typically moderate, 12-20p on most days. Running appliances here is fine if overnight isn't possible, but it's always more expensive than the overnight window.
The key number to hold in your head is the July 2026 price cap rate: 26.11p/kWh. Any Agile slot below that number is already cheaper than a standard tariff. Overnight slots at 3-6p are roughly 80% cheaper. That comparison is what makes the habit worth building.
Using tomorrow's prices to set tonight's timers
The practical payoff from checking prices comes from matching your delay timers to the cheap windows. This is simpler than it sounds.
Check the dashboard after 4pm. Identify the cheapest two to three hours overnight for your region. Then set your appliances accordingly.
Washing machine and dishwasher. Use the delay-start function. Most modern machines have a button or dial to set a start delay in hours. If the cheapest window is 2am to 5am, set your machine to start at 2am before you go to bed. It will run, finish, and be ready to unload in the morning. You used electricity at 3p instead of 26p. On a daily cycle, that saving compounds to over £200 a year.
EV charger. Most home EV chargers, and most car apps, allow you to set a charge schedule. Set the start time to the beginning of the overnight cheap window and the target state of charge to suit your needs. Some chargers and cars can be configured to follow Agile prices automatically using the Octopus API or integrations like Ohme, Indra, and Hypervolt. See the full appliance timing guide for EV-specific setup.
Tumble dryer. Run it overnight if it has a delay start. If not, run it during the mid-morning lull, typically 9-11am, when prices are often still lower than the evening peak.
Immersion heater and heat pump. Both benefit enormously from overnight scheduling. An immersion heater running for two hours overnight at 4p/kWh costs 8-16p depending on size. The same run at 6pm costs 50-100p. Over a year, the difference is over £100 on the immersion alone.
The night you set these timers is the night Agile starts working. Every subsequent day it runs in the background, quietly moving your biggest costs to the cheapest slots without you doing anything at all.
What to do when prices aren't published yet
Before 4pm, only the current day's prices are fully confirmed. If you check the dashboard before prices have landed, you'll see today's remaining slots clearly and tomorrow's slots either blank or showing estimated/forecast values.
If it's before 4pm and you need to run something now, use today's current prices. The dashboard shows the live rate for the current half-hour and all remaining slots for today. If the current rate is low, run the appliance now. If it's high, wait until you can check tomorrow's overnight prices after 4pm.
On the rare occasions when prices are delayed past 5pm, it usually means a market data or API issue. In these cases, the previous day's price pattern is a reasonable guide: overnight will almost certainly be cheap, the 5-8pm peak will almost certainly be the most expensive, and it's safe to set timers to the 11pm to 6am window with confidence.