The Intelligent Octopus Go Charge Cap limits your EV to a maximum of six hours of cheaper smart charging each day.
Once your car has used those six hours, any additional EV charging can be charged at your normal peak rate, even if it happens during the usual 11:30pm to 5:30am off-peak period.
This does not mean your home loses its six-hour overnight cheap window. Your household electricity is still guaranteed the off-peak rate between 11:30pm and 5:30am every night. The six-hour Charge Cap applies specifically to your EV charging.
This distinction is the most important thing to understand about how Intelligent Octopus Go now works.
You can also read our Intelligent Octopus Go guide for current rates, eligibility and a full explanation of how the tariff works.
How does the Intelligent Octopus Go six-hour limit work?
Your EV can receive up to six hours of cheaper managed charging each day, measured from midday to midday. Your home’s guaranteed 11:30pm–5:30am off-peak window is separate and does not get reduced if Octopus schedules your EV to charge during the day.
Intelligent Octopus Go effectively treats your household electricity and EV charging separately.
There are now four types of electricity usage:
| Usage | What it means |
|---|---|
| Peak home usage | Electricity used by your home outside a qualifying off-peak period |
| Off-peak home usage | Electricity used between 11:30pm and 5:30am, plus qualifying extra smart-charging periods |
| Peak EV usage | EV charging that does not qualify for the cheaper smart-charging rate |
| Off-peak EV usage | Up to six hours of qualifying smart EV charging |
Octopus describes this as a four-rate system, separating the electricity used by your car from the electricity used by the rest of your home.
The important part is that your home and your EV no longer necessarily pay the same rate at the same time.
Your home always receives the cheaper rate between 11:30pm and 5:30am.
Your EV receives up to six hours of cheaper managed charging per day, which Octopus measures from midday to midday. Those six hours could happen overnight, during the day, or across several different charging periods depending on the schedule Octopus creates for your car.
Your home still gets six cheap hours every night
One of the easiest mistakes to make is assuming that the Charge Cap has removed Intelligent Octopus Go’s normal six-hour off-peak window.
It hasn’t.
Your home is still guaranteed cheaper electricity between 11:30pm and 5:30am every night, whether your EV is charging or not.
So you can still schedule things such as your washing machine, dishwasher or home battery around this overnight period if appropriate.
The change is that your EV has its own separate six-hour cheap charging allowance.
That means 11:30pm arriving does not automatically give your EV another six hours of cheap charging if it has already used its allowance earlier in the day.
An example makes the Charge Cap much easier to understand
Imagine you plug your EV in during the afternoon and Octopus decides the best time to smart charge it is:
1:00pm to 7:00pm
That is six hours of smart charging.
Because Octopus scheduled the charging, your EV receives the off-peak rate for those six hours. Your home also receives the off-peak rate during those qualifying smart-charging periods, even though they are outside the normal overnight window.
By 7:00pm, however, your EV has used its full six-hour cheap charging allowance.
At 11:30pm, the normal Intelligent Octopus Go overnight period begins.
Your home now gets cheap electricity between 11:30pm and 5:30am as usual.
But your EV has already used its six-hour allowance.
If the car charges again after 11:30pm, that additional EV charging can therefore be charged at the peak EV rate, while electricity being used by the rest of your home is still charged at the off-peak home rate. Octopus specifically confirms that EV charging above the six-hour allowance can revert to the standard rate even when it happens during the home’s overnight off-peak window.
So at, say, 1:00am, you could have:
- your dishwasher using electricity at the off-peak rate
- your washing machine using electricity at the off-peak rate
- the rest of your household usage at the off-peak rate
- your EV charging at the peak rate
That might initially sound strange, but it is possible because Octopus can now separate your EV charging from the rest of your household consumption.
What actually is Charge Cap?
The six-hour limit and Charge Cap are closely related, but they are not quite the same thing.
The six-hour limit is the tariff rule: your EV gets up to six hours of cheaper managed charging per day.
Charge Cap is an optional feature designed to stop you accidentally charging beyond that allowance at the more expensive rate.
If Charge Cap is available on your account and you switch it on, Octopus says your car will automatically stop charging before it begins incurring the peak charging rate. You can find the setting within the device settings in the Octopus Energy app where it has been enabled.
This is particularly useful if you would rather your EV stop charging than continue charging at the higher price.
What happens if I need more than six hours of EV charging?
You can still request enough charge to reach the battery level you need.
However, if the car needs more than six hours of managed charging, the first six hours can receive the off-peak rate and additional charging can be billed at the peak rate.
For example:
Seven hours required
- First six hours: off-peak EV rate
- Final hour: peak EV rate
The timing of that final hour does not necessarily change this. If the seventh hour happens at 2:00am, your home can still be on its cheap overnight rate while the EV is charged at the peak EV rate.
If you have Charge Cap enabled, the car can instead stop before moving onto the expensive rate.
Do daytime smart charging slots still make your whole home cheaper?
Yes.
This is still one of the major benefits of Intelligent Octopus Go.
If Octopus schedules your EV to smart charge outside the normal 11:30pm to 5:30am period, your household electricity also receives the off-peak rate during those qualifying half-hour periods, provided the EV charging is still within its six-hour allowance.
For example, if Octopus schedules smart charging between:
2:00pm and 4:00pm
your EV receives the cheap rate during that period and your household electricity also receives the cheap rate.
You would then still receive the normal household off-peak period between 11:30pm and 5:30am that night.
The daytime smart-charging slot does not use up your home’s overnight six-hour window. It uses part of your EV’s separate six-hour charging allowance.
When does the six-hour EV charging allowance reset?
Octopus measures the six-hour EV charging allowance from midday to midday, rather than midnight to midnight.
This is worth remembering when looking at charging that crosses midnight because the calculation does not simply reset when the date changes at 12:00am.
Does being plugged in count towards the six hours?
No.
Only the time your EV is actually being smart charged counts towards the six-hour allowance.
If your car is plugged in for ten hours but Octopus only actively charges it for four of those hours, only those four hours count towards the limit.
This is one reason it can be better to leave Intelligent Octopus Go in control rather than trying to predict when the car will charge yourself.
Is it six hours or twelve half-hour charging slots?
The cap is based on the actual amount of time your EV is charged, rather than simply counting six hours’ worth of half-hour billing periods.
Octopus still bills electricity in half-hourly periods. For example, if the car charges for only part of a particular half hour, that half-hour period can still be billed at the relevant off-peak rate. But the EV charging allowance itself looks at the amount of time the car was actually charging.
Why has Intelligent Octopus Go introduced the six-hour cap?
Intelligent Octopus Go is designed around Octopus controlling when compatible EVs charge.
Rather than guaranteeing unlimited cheap smart charging whenever a car is connected, the tariff now provides up to six hours of discounted managed EV charging each day.
Octopus says more than 80% of its EV charging sessions take less than six hours, so the allowance is designed to cover the normal charging requirements of most customers.
For drivers who regularly arrive home with a very low battery and need substantially more than six hours of charging, however, the cap is more important to understand.
Does the Charge Cap make Intelligent Octopus Go worse?
For most drivers, the six-hour limit may make little difference if their normal charging sessions are comfortably below six hours.
The main change is that it is no longer safe to think of Intelligent Octopus Go simply as “cheap EV charging whenever Octopus schedules it.”
There are now two separate things to remember:
Your home: guaranteed off-peak electricity from 11:30pm to 5:30am.
Your EV: up to six hours of cheaper smart charging per day.
If Octopus schedules some of your EV charging outside the overnight window, you can still benefit from extra cheap household electricity during those periods. But once the EV has used its six-hour allowance, additional charging can become considerably more expensive.
You can read our full Intelligent Octopus Go guide for current tariff rates, eligibility, compatible cars and chargers, and a wider explanation of how the tariff works.
Intelligent Octopus Go Charge Cap FAQs
Is Intelligent Octopus Go still cheap from 11:30pm to 5:30am?
Yes. Your home electricity is still guaranteed the tariff’s off-peak rate between 11:30pm and 5:30am every night.
Your EV is treated separately and has a maximum of six hours of qualifying cheap smart charging per day.
Does my EV automatically get the cheap rate between 11:30pm and 5:30am?
Not necessarily.
If your EV still has some of its six-hour smart-charging allowance remaining, qualifying charging during this period can receive the off-peak rate.
However, if your EV has already used its full six-hour allowance, further EV charging can be charged at the peak rate even though the rest of your home is currently receiving cheap electricity.
Can my home and car be charged different electricity rates at the same time?
Yes.
The four-rate billing system separates home consumption from EV consumption. This means your home could be receiving the off-peak rate while your EV is charged the peak rate, or both your home and EV could receive the off-peak rate during a qualifying daytime smart-charging period.
What happens when I reach six hours of charging?
Once the EV’s six-hour cheap charging allowance has been used, additional charging can be billed at the peak rate.
If Charge Cap is available and enabled, it is designed to stop your EV charging before it begins using electricity at the expensive rate.
Does the six-hour cap include time when the car is plugged in but not charging?
No. Only the time the EV is actually being smart charged counts towards the limit.
Should I turn Charge Cap on?
If you do not normally need more than six hours of charging, Charge Cap can be useful because it helps prevent your EV accidentally continuing to charge at the peak rate.
If you occasionally need a larger charge and getting enough range is more important than avoiding the peak rate, you may prefer to allow the car to continue charging when required.
The important thing is to understand the trade-off before requesting more than six hours of charging.