What Are Time of Use Tariffs?

What Are Time of Use Tariffs (ToU)?

If you are here because you asked Google the question, “What are Time of Use Tariffs?”, then you’ve come to the right place.

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 all starts with understanding Time of Use (ToU) tariffs and how smart meters are your best friends in this game.

Especially if you have solar panels, batteries, EVs, or a heat pump, you’re in a prime spot to save loads of cash.

Let’s break it down.

Reading Guide

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.

Overview of Octopus Time-of-Use Tariffs

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.

So What are Time of Use Tariffs?

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 Is This Happening?

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.

The Role of Smart Meters

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.

Got Solar Panels? Time to Maximise Your Sunshine

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

Home Battery Owners: You’re Basically Playing the Grid Like a Game

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 Owners: Way Cheaper Than Petrol and Even Get Paid to Charge Your Car?

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 Pump Owners: Yes, You Can Save Too

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: Smart Time-of-Use Tariff for Heat Pump Users

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

Downsides?  There Are a Few…….

• 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.

Final Thoughts

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 are time-of-use tariffs in the UK?

Time-of-use (TOU) tariffs charge different electricity prices depending on the time of day. Peak periods such as early evening are more expensive, while overnight or off-peak periods are cheaper. They are designed to encourage households to shift usage to times when the grid is under less pressure.

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

Yes, most modern TOU and smart tariffs require a smart meter that can record half-hourly consumption. Without one, you may only be able to access older two-rate tariffs such as Economy 7 or Economy 10.

When are off-peak electricity times?

Off-peak times vary by supplier and tariff. Economy 7 typically offers seven cheaper night hours (often between 11pm and 7am). Smart TOU tariffs such as Octopus Go or Agile can have specific overnight windows or half-hourly prices that change daily. Always check your supplier’s tariff details.

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

Economy 7 and Economy 10 are fixed two-rate tariffs with set night hours. Modern smart tariffs are more flexible, with multiple time bands or half-hourly rates that follow wholesale prices. This creates more savings potential if you can move usage but also more risk if you use energy at peak times.

Which households benefit most from TOU tariffs?

Homes with high overnight or flexible demand, such as those with electric vehicles, heat pumps, storage heaters, solar panels and batteries, usually benefit most. If you can automate usage to run at night or off-peak, a TOU tariff can lower your bills significantly.

Can time-of-use tariffs save me money?

Yes, if you can shift significant usage to cheaper periods. For example, EV charging, laundry, or immersion heaters run overnight can cost much less. If most of your use is in the evening peak, however, your bills could increase compared to a flat-rate tariff.

What is the difference between static and dynamic smart tariffs?

Static TOU tariffs use fixed peak and off-peak windows, such as Economy 7 or Octopus Go. Dynamic tariffs like Octopus Agile set prices half-hourly and publish them daily, reflecting wholesale market conditions. This can lead to very low rates when renewables are abundant, but higher rates during peak demand.

Is electricity always cheaper at night?

Not always. Traditional tariffs like Economy 7 guarantee cheaper night rates. Dynamic tariffs may also offer cheap or even negative prices at night, but this isn’t guaranteed every day. Check your tariff’s terms and daily prices.

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

Yes. Standing charges are daily fixed costs added to your bill, regardless of when you use electricity. They vary by supplier and tariff, and you should include them when comparing TOU tariffs with flat-rate plans.

What happens to older RTS meters and Economy 7 tariffs?

The Radio Teleswitch Service (RTS), which controls some Economy 7 and Economy 10 meters, is being phased out. If you have an RTS meter, your supplier will upgrade you to a smart meter so you can continue to access multi-rate or smart TOU tariffs.