UK Time of Use Tariffs: Cut Your Energy Bill

What Is a Time of Use Tariff and How Does It Work?

A time-of-use (ToU) tariff is an electricity plan where prices change depending on when you use power. It’s cheaper when demand is low and higher at peak times. These tariffs help households save money and make better use of renewable energy.

Let’s be real, energy bills in the UK haven’t exactly been a source of joy lately. But there’s a smarter way to take control, and it starts with understanding how ToU tariffs and smart meters work together. If you have solar panels, a home battery, an EV, or a heat pump, you’re in a great position to save even more.

Let’s break it down.

Table of Contents

This article is a comprehensive read, drawing on both data and hands-on testing.

Use the Table of Contents below to jump straight to the questions that matter most — or scroll through at your own pace.

Octopus Time of Use Tariffs Explained

Octopus Energy offers several time-of-use tariffs designed to reward flexibility and help customers save money when they shift usage to off-peak hours. Here’s a quick overview of the main options:

• Agile — tracks the day-ahead wholesale market, with prices updating every 30 minutes.

• Go — overnight low rates, ideal for EV charging.

• Intelligent Go — smart-scheduled EV charging, automatically shifting to the cheapest hours.

• Cosy — discounted time bands for heating and comfort at home.

• Flux — for solar and battery users, offering premium export rates at peak times.

• Tracker — a daily rate that moves with the wholesale market, offering transparency and value when prices fall.

Each of these tariffs encourages demand response — shifting energy use to cheaper, off-peak periods. This not only helps households cut costs but also supports a more flexible grid that makes better use of renewable energy.

If you do decide to change your supplier to Octopus Energy, you can claim £50 free credit when switching using my referral link. Thank you if you decide to do that.

Understanding Time of Use Tariffs in the UK

A time of use tariff (ToU) means the cost of electricity changes throughout the day. Instead of paying a flat rate 24/7, the price varies—often cheaper at night or during times when the grid is under less pressure.

Think of it like off-peak train travel, but for your home’s electricity.

Why Time of Use Tariffs Exist in the UK

Because the energy grid is getting smarter—and greener. As we add more renewable energy like wind and solar into the UK generation mix, we need to be a bit more flexible about when we use power.

Wind turbines don’t spin on demand, and the sun doesn’t care about your dinner plans. Sometimes there’s loads of clean, green energy buzzing around the grid, and other times… not so much. By encouraging people to shift their electricity use to those “greener” hours, we can reduce the need for fossil fuels.

So yeah, using your dishwasher at 2 am might actually help save the planet and a save a few quid at the same time.

Time of Use Tariffs Are Not Exactly a New Thing!

Economy 7 and Economy 10 were early time-of-use electricity tariffs introduced in the UK to encourage households to use electricity during off-peak hours, when demand on the grid was lower and electricity was cheaper to generate.

Economy 7 offered seven hours of discounted electricity overnight, while Economy 10 provided ten off-peak hours spread across night, afternoon, and early morning periods—benefiting homes with electric heating systems.

These legacy tariffs were controlled by traditional mechanical meters and fixed time schedules.

How Smart Meters Make Time of Use Tariffs Work

Here’s the kicker: without a smart meter, none of this works.

Smart meters track your electricity usage in real-time (round it up in 30 minute segments) and send that data to your supplier. That’s how suppliers like Octopus Energy can charge you different rates depending on the time of day.

No more estimated bills. No more overpaying.

Right now, Octopus Energy have the largest range of Time of Use tariffs in the UK.

If you’re thinking of switching energy suppliers, homeowners that use this referral code can claim £50 of free Octopus Energy credit after signup: https://mickwall.octopus.energy

Business users that signup using the same code with be granted £100 of free credit.

How Solar Panels Benefit from Time of Use Tariffs

If you’ve got solar panels on your roof, ToU tariffs let you squeeze even more value out of them.

• Sell at the right time: With tariffs like Octopus Outgoing, you can currently export surplus energy back to the grid when prices are high. Sometimes, you can earn more than 15p/kWh (or more during peak demand events).
• Shift your usage: Run dishwashers, washing machines, or charge batteries during low-rate times to keep your bill even lower.

More information about Octopus Outgoing tariffs and pricing for your region can be found here:

Octopus Outgoing Export Pricing

Using Home Batteries with Time of Use Tariffs

If you’ve invested in a battery (like a Tesla Powerwall, Sigenergy, GivEnergy or any battery system), Time of Use tariffs are where it really gets fun.

• Charge when it’s cheap: Use tariffs like Octopus Flux to charge your battery during low-rate times.
• Discharge when it’s pricey: Some smart setups can automatically export back to the grid during peak pricing periods. That’s free money.

Smart battery + smart meter + smart tariff = you’re smarter than your bill.

More information about Octopus Flux tariff and pricing for your region can be found here:

Octopus Flux Yorkshire

EV Charging on Time of Use Tariffs

Yep, sounds mad—but it’s true.

With Octopus Go and Intelligent Go, you can charge your EV overnight at crazy low rates (as low as 7p/kWh at times). That’s around £5 for a full charge to get 300 miles —goodbye, petrol station misery.

• Intelligent Octopus even optimises your charging for you.  Plug it in when you get home from work and Intelligent will take care of charging at the right time and your EV will be charged to your desired amount by the next morning.
• Want to get even nerdier? Combine with the Octopus Agile tariff and charge when prices drop—sometimes you might even get paid to use electricity when the grid is overloaded.

More information about Octopus Intelligent Go tariff and pricing for your region can be found here:

Intelligent Go

Heat Pumps and Time of Use Tariffs

Heat pumps are amazing for cutting carbon, but they do draw quite a bit of electricity. That’s where shifting your heating schedule to off-peak times becomes key.

• Use Octopus Cosy to pre-heat your home or hot water tank during low-cost periods.
• Some heat pumps can be paired with smart thermostats and schedules to do this automatically.

It’s like setting your house to pre-toast itself when electricity is cheap.

Octopus Cosy Tariff has 3 price dips that you can take advantage of.

More information about Octopus Cosy tariff and pricing for your region can be found here:

Octopus Cosy Heat Pump Tariff | Times, Rates and FAQ

We also wrote an article entitled “Best Heat Pump Tariff” where we looked at all the options available based on the technology you may have in your home.

Best Heat Pump Tariff

Octopus Agile – The Ultimate Time of Use Tariff

Agile is a tariff from Octopus Energy that is based on the underlying price of wholesale electricity.  And this is called the ultimate ToU tariff as the price changes each and every 30 minutes of the day.

So because there are 48 different pricing slots per day it does require active management to maximize savings.

In this example below you can see there were a lot of renewable on this day (5th August 2025).  And as such there were almost 14 hours of continuous negative priced energy where customers were being paid to take electricity off the grid.

More information about Octopus Agile tariff and pricing for your region can be found here:

Octopus Agile Tariff Pricing

Disadvantages of Time of Use Tariffs

• Needs smart tech: You’ll need a smart meter, a compatible EV charger, and ideally a smart battery or heat pump controller.
• Lifestyle tweaks: It works best if you’re flexible—running the dishwasher at midnight, scheduling your tumble dryer during the off-peak window, etc.
• Not every tariff fits every household: Some ToU tariffs have limited off-peak windows or don’t align with your usage. Also, some are only available if you have certain technology in your home (EV, Heat Pump etc).

Further Reading: Wholesale Energy Pricing

Want to understand what drives these tariffs behind the scenes? Our Wholesale Energy Pricing guide explains how the futures market, day-ahead auctions, and even concepts like marginal pricing shape UK electricity costs.

You’ll also find graphs, dashboards, and downloadable CSV data if you want to explore how wholesale prices move over time.

Are Time of Use Tariffs Worth It?

Does this all help answer the question, “What Are Time of Use Tariffs?”

Time of Use tariffs aren’t just some boring energy tech—they’re a way to take control, save money, and even earn a bit back. And with a smart meter in place, you unlock all of it.

Octopus Energy is leading the charge in the UK, offering flexible tariffs that actually reward you for being smart about when you use electricity.

So if you’ve got solar, a battery, an EV, or a heat pump—or you’re just looking to shrink that energy bill—ToU tariffs might be the energy hack you’ve been waiting for.

Time of Use Tariffs – Frequently Asked Questions

What is a time-of-use tariff in the UK?

A time-of-use (ToU) tariff is an electricity plan where prices change depending on when you use power. Peak hours such as early evening cost more, while off-peak or overnight periods are cheaper. They help balance demand and reward households that can shift usage.

Do I need a smart meter for a time-of-use tariff?

Yes. Most ToU or smart tariffs need a smart meter that records half-hourly use. Without one, you can usually only get older two-rate tariffs such as Economy 7 or Economy 10.

When are off-peak electricity times in the UK?

Off-peak hours depend on your supplier and tariff. Economy 7 usually gives seven cheaper night hours (around 11 pm – 7 am). Smart tariffs like Octopus Go or Agile have specific overnight windows or half-hourly prices that change daily.

How do time-of-use tariffs compare with Economy 7 or Economy 10?

Economy 7 and 10 have fixed night periods. Modern smart ToU tariffs are more flexible, using multiple time bands or half-hourly prices that follow the wholesale market. That means bigger savings if you move usage, but higher costs if you don’t.

Which households save the most with time-of-use tariffs?

Homes that can use power overnight or flexibly benefit most. That includes households with EVs, heat pumps, storage heaters, solar panels, or batteries. Automating usage during cheap periods can cut bills significantly.

Can a time-of-use tariff save me money?

Yes, if you can shift enough usage to cheaper hours. Running an EV charger, washing machine, or immersion heater overnight can cost far less. If most of your use is at peak times, a flat-rate tariff might still be cheaper.

What is the difference between static and dynamic smart tariffs?

Static tariffs use fixed peak and off-peak windows, such as Economy 7 or Octopus Go. Dynamic tariffs like Octopus Agile change every 30 minutes based on wholesale prices. They can be very cheap when renewables are abundant and higher during evening peaks.

Is electricity always cheaper at night?

Not always. Traditional tariffs like Economy 7 guarantee lower night rates, but dynamic ones can vary daily. Sometimes you’ll see negative prices at night, but it depends on grid conditions and renewable output.

Do standing charges apply to time-of-use tariffs?

Yes. Standing charges are a daily fixed cost added to your bill no matter when you use power. They differ by supplier and should be included when comparing tariffs.

What happens to old RTS meters and Economy 7 tariffs?

The Radio Teleswitch Service (RTS) that controls some Economy 7 and 10 meters is being phased out. Suppliers will upgrade affected homes to smart meters so customers can stay on multi-rate or smart ToU tariffs.