Energy Comparison Sites – Guide to Compare Gas and Electricity Prices Online

What are energy comparison sites?

Energy comparison sites have been set up to allow consumers to quickly and easily find the best energy deals for them. You simply put in a couple of basic details about their location, energy use and current supplier, and the comparison site calculates which energy suppliers could save you money on their annual energy bill. On average, by using a price comparison site a homeowner could save between £150-£300 a year by being energy-savvy and checking comparison websites for the latest money saving deals.

How do energy comparison sites work?

As briefly touched on above an energy comparison site works by taking your details and estimated energy use details and then compares your current deal to all the other energy supplier tariffs in the UK. By default, these are listed in the order of tariffs that offer the largest savings for you. Energy comparison sites essentially work as a middleman between the consumer and energy suppliers. In a world where it’s impractical to contact each energy supplier individually due to the vast and growing choices available, this is the quickest way to get an overview of the energy tariffs available to your address.

Which is the best energy comparison website?

When you search google for “energy comparison sites” you’ll get numerous hits from multiple comparison sites claiming to offer the biggest and best savings. But which ones are the best? Does it matter which one you use? They all have their merits, let’s take a more detailed look at six of the most used energy comparison sites:

Go Compare

This well-known comparison site claims that you could save up to £302 on your combined energy bill. They are also rated excellent by Trustpilot with a score of 4.8. As you would expect, their website is easy to use and you will receive comparison prices in minutes.

Compare the Market

Another comparison site giant, they claim that they could save you up to £338 on your energy bills. Plus you get the added bonus of 2 for 1 cinema tickets and other money saving perks. They don’t rate well on Trustpilot, scoring a poor rating of 2.8 with mixed reviews of consumers.


MoneySuperMarket claims to slash at least £306 off your energy bill. The small print states that at least 30% of users achieved this level of saving. MoneySuperMarket is rated excellent at 4.5 on Trustpilot with some glowing reviews.


This popular brand claims to save consumers on average £216 per year on their energy bills. They also rate well on Trustpilot reviews, scoring excellent at 4.7 with a series of positive reviews. state they save their customers a minimum of £144.95 per year on their dual fuel bill. Whilst this appears modest, it’s possibly a more realistic figure than others. Competitors have cherry picked their highest saving quotes instead of looking at the average. They score well on Trustpilot too with another excellent rating and an overall score of 4.3.

Energy Helpline

This comparison site states it wants you to gain serious savings. They claim buyers could slash their bills by as much as £497 a year by using their switching service. They also score well with another excellent rating and an overall Trustpilot score of 4.5.

Taking the above into account, it’s too close to call to say one comparison site is miles better than the others. It may be a good idea to run your details through a couple of them to see which ones give you the best overall saving. At most this will only take you an additional couple of minutes. Five of the comparison sites clearly have better customer service feedback, which is where compare the market has fallen short

How much could I save by switching?

According to the Money Advice Service, the average household can save up to £300 a year by switching. You could save even more than this by being more efficient with your gas and electricity use. Of course, this number will depend on various factors including energy consumption, type of property and the type of energy you require to heat your home (dual-fuel, gas only, or electric only). When you run a comparison search you’ll see the estimated savings for your property in the search results.

Switchable tariffs and whole market comparisons – What’s the difference?

When you input your details into an energy comparison website and press “search” you’ll get a list generated of all the available tariffs that you can switch through the particular comparison website you are using. These are known as switchable tariffs. In the menu, if you navigate through the filters you will usually find an option that says “show me all” or “whole market tariffs”. This filter will show you all the energy tariffs available to your location regardless of if you can use that comparison site to switch to them or not.

All the market deals

When you select the whole market or show all available tariffs you are presented with more options, and we would always recommend you do this so you are not just limited to the ones that the comparison site gets a commission for when you sign up to switch through their link.

The downsides of this are if you choose a supplier who isn’t on their switchable list you will have to visit the supplier’s website directly to sign up and so you may not qualify for any incentive the comparison website is offering. You should weigh up which gives you the greater financial benefit before switching.

Which comparison sites are whole market?

They all are. You just need to be savvy when searching to make sure you press the “show me everything” button, or “show the whole market”. Some energy comparison websites host a handful of deals that are exclusive to them which you won’t find on other comparison websites.

How long does it take to do an energy comparison?

Energy comparison websites are very easy to use. Even if you do not have your energy bill to hand by inputting a few simple details such as your postcode, current energy usage or energy spend and supplier details you can have a list of energy comparison quotes in only 3-4 minutes.

What paperwork do I need ready to do an online energy comparison?

To get your initial energy comparison prices you don’t actually need anything. If you do have an energy bill handy you’ll most likely get a more accurate price than if you input your spend per month. If you do not know the cost of your energy it can even estimate a price for you. This is calculated by asking how many bedrooms your property has and how you use energy. This is useful if you are about to move home and don’t yet know the energy cost but would like to get an idea of available tariffs.

What information do I need to tell them and why?

To compare energy prices, the comparison website will need some basic details from you to be able to provide accurate price estimates:

Your address

This is important to find out which suppliers are available in your area. While most are UK wide, some only cover certain regions.

What type of energy do you use?

This important factor will affect which tariffs are best for your property, whether it is dual fuel (gas and electricity), gas only, or electric only.

Who is your current supplier?

This is to help you select your current tariff. Comparison sites have a list of all tariffs available by each energy provider, so it allows you to easily narrow down which tariff you are on.

What your current tariff is called

Without this the comparison website won’t know what it is making a comparison against and hence will not be able to tell you how much you could be saving. The tariff tells them how much you are paying per unit and if there is a standing charge with your current supplier’s tariff and if it is a fixed or variable price.

Whether you pay by cash, direct debit or prepayment meter

Most energy companies have many tariffs available and depending on the payment method you use these could save you money. Tariffs which can be paid by direct debit tend to be more competitively priced than those which involve cash or prepayment meters; this is largely due to the amount of extra admin and maintenance work required for the other two methods.

How much you spend on energy

This allows the comparison site work out how much energy you are using, so it can then estimate how much you could pay by switching to a different provider. You can either input the details from your bill for a more accurate number or if you know roughly what your spend is in £ you can input that instead.

Email address

This is partly for data capture, but also so the comparison website can send you an email with a list of your top energy switching tariffs. Usually with a link, so you can get back to your energy comparison quotes in a click. Some comparison sites now have this as an optional field so you don’t have to provide it. Consider how likely you are to want to recall saved quotes instantly later.

How do I find the cheapest energy supplier on comparison sites?

As we briefly touched on above when you go on an energy comparison website and view your results, there are filters at the top or left-hand side depending on the website, and there is an option that says “show me everything” or “show the whole market”. This will give you a list of every energy supplier available to you. It’s usually sorted automatically from the cheapest to the highest, so the lowest tariff should be top of the list. You can then filter further as you wish.

What options can I filter by and what do they mean?

When you look at the filters on a price comparison site you’re likely to see a number of filters you can tick, while some are self-explanatory, if you are unsure what they mean here’s a brief overview:

Green Energy: These tariffs use 100% renewable energy sources to provide power including wind, solar power and the power of the tide. These are sources of power that will never run out unlike fossil fuels.

Rewards: Some energy suppliers offer incentives with their tariffs that can range from discounts to free gift vouchers, tickets to events or cash back.

Energy switch guarantee: This has been set up to provide a hassle free and seamless switch to the new supplier in only 21 days. You also get a 14-day cooling off period under the guarantee and if you change your mind you will stay on your existing tariff with your current supplier. When you switch, any credit on your old tariff will be returned to you within 14 days of receiving your final bill.

No exit fees: An exit fee is a charge your supplier can impose when you leave them before your existing contract ends. Because more and more people are opting to switch energy suppliers to save money more regularly, some suppliers are now offering no exit fees to entice new customers. If you have an exit fee on your current tariff, it’s worth checking if you could still save more by switching and paying the exit fee rather than being stuck on an expensive tariff for months and months.

Paper billing: In an effort to be greener, most utility companies now use paperless billing. This is where the customer is either emailed their bill or it is downloadable by logging into the supplier’s website. Some people still prefer to have a physical paper bill sent through the post and most companies will still offer this for a small monthly fee.

What sort of energy tariff should I choose?

When looking at energy tariffs there are essentially two options, fixed or variable. In order to understand which is better, let’s look at them independently:

Fixed tariff

A fixed tariff is a contract you enter into with your energy supplier for a set period of time. The agreement will state what your unit price will be fixed at for that length of time (usually 12-18 months is typical). The obvious benefit of this is you know what you are paying per unit for that set period of time. It will never be more, and on the flip side, it won’t ever be less either!

Variable tariff

This type of tariff can go up or down at any time while you are with the supplier. The prices are usually in some way linked to wholesale energy prices at that time. Your energy supplier should notify you when the prices change if you are on a variable tariff especially when they go up.

So which is better? Fixed tariffs offer you a level of security. You will know exactly what you are paying for the terms of your contract, there will be no nasty surprises. If you are the sort of person who prefers to take a chance, you could save money by being on a variable tariff. Variable tariffs offer no guarantees of stability in the pricing however.

What payment method should I choose?

When you look at switching energy suppliers, one of the questions on comparison sites is how you prefer to be billed. The standard options are monthly, quarterly or on receipt of a bill. But what difference does this make to you?

Monthly or quarterly direct debit

This is an arrangement you will make with your new energy supplier for a set amount to be taken either on the same day each month or every three months depending on how you like to handle your bills. The amount per month will be your supplier’s estimate of how much energy you are likely to use across the next twelve months and they can adjust this up and down if your usage changes. Some people prefer to pay monthly or quarterly because you know you are paying off the bill in manageable chunks instead of receiving a hefty bill once or twice a year that you need to find the money for. Paying by direct debit usually equals being able to choose from the best deals available.

On receipt of the bill

If you like to keep things traditional you might prefer to receive your yearly or twice-yearly energy bill and clear it all in one go by paying either online or over the phone by card or alternatively cash or cheque at the post office or by post. This works for some people but others do not like being hit with an enormous bill once or twice a year.

Prepayment meters

When you use a prepayment meter you are essentially paying for your energy before you use it. The benefit of this is you never receive a bill for extra energy charges but it’s your responsibility to top up the key or card so you have enough gas and electricity to keep your home warm and electrical items operating. This also means you are fully in control of your energy consumption and you can tell when you are spending more than usual. The principal disadvantage of this type of payment arrangement is that prepayment tariffs are amongst the least attractive price wise that suppliers offer. You’ll probably be paying more per unit overall.

Are all energy suppliers on energy comparison websites?

Yes they are, but not all tariffs are shown on the comparison sites. Some suppliers do not have an agreement in place for all comparison sites to show all their tariffs and this is the reason you don’t get to see everything. For example, e.on are on all comparison websites but their product E.ON Next is not on comparison websites. Some comparison sites also have exclusive tariffs to them from certain suppliers that can’t be found on other comparison websites.

Are there any hidden costs of using a energy comparison website?

There are no direct costs to you as the consumer, it’s a completely free service. Comparison websites make money through agreements with the energy suppliers, and advertising so you don’t pay a penny for using their service.

Do some energy comparison sites have exclusive tariffs that are only available to that site?

Yes, some energy suppliers offer exclusive tariffs through comparison sites that you won’t find on any other competitor comparison websites. These are deals they have established with the energy suppliers directly and no-one else can offer the same tariff. For this reason it’s worth checking a couple of price comparison websites, simply because a deal is exclusive does not mean it offers the greatest savings.

How do energy comparison sites make money?

Energy comparison websites make their money by charging the energy supplier a small commission or fee when you choose to switch to them through their comparison website for facilitating the switch. They also earn money through banner advertising where energy suppliers or other companies pay to display an advert on their website for a monthly fee.

What happens after I start my switch?

When you have chosen your new tariff (if it is one you can switch to through the comparison site), you’ll be taken to the next step which is to confirm your personal details and how you want to pay for your new tariff. Then the switching process will start, your new energy supplier will be in touch to confirm your switch-over date. In most straightforward cases the switch over will take between 17-21 days. If you change your mind about the switch you have a 14-day cooling off period to withdraw from the agreement. It’s important if you do change your mind that you contact your supplier to cancel any contract you have entered into. If you are happy to go ahead, your switch should be fairly seamless and complete within 3 weeks.

Which is the cheapest energy supplier?

There’s no definitive one size that fits all cheapest energy tariff or energy suppliers out there. The best deal for you will depend on the energy type you use, how you pay, your overall consumption and where you live. The supplier with the cheapest prices is likely to change month to month. Energy prices are something that’s worth keeping an eye on. Some websites offer a monitoring service where they alert you if you could benefit from changing tariff based on your previous search criteria.

Switching FAQs  

Why switch energy suppliers?

Because in most cases you will save money by switching energy suppliers. You can change energy suppliers every 28 days as a minimum. The most energy savvy switchers tend to change tariffs once or twice a year to take advantage of the best deals.  

When should I switch energy?

This depends on your current situation. There are a few answers to this question depending on where you are in your energy switching journey:

If you haven’t switched suppliers in a while, the best time for you could be right now. By switching you’re likely to discover you have been paying way over the odds for way too long. 

When your current supplier is about to impose a price increase it might be an opportune time to shop around. If one of the big 6 suppliers puts their prices up you can be certain the other 5 will follow. Switching to get locked into a money-saving fixed tariff could be the answer.

Are you wondering if there is a time of year that’s best for switching? We would recommend shopping around late summer/autumn. Get yourself switched to a competitive energy deal before the cold winter months arrive to ensure you won’t be paying over the odds when your energy consumption is at its highest.

Will it cost me anything to switch?

You’ll need to check your existing contract for the definitive answer for this. If you are out of contract then there you won’t see a charge. Some energy suppliers offer tariffs with no early exit fees. These are excellent for those that like to regularly shop around. Some suppliers or tariffs will carry an early exit fee which is a fixed amount payable for ending the contract with them early to switch suppliers. It’s always worth running the numbers to weigh up if switching tariffs is still worth doing. Even if it does mean having to foot the bill of an early exit fee.

How long does it take to switch energy suppliers?

21 days or less. Once you’ve picked your tariff and given your new supplier your details, the switching process starts. In most cases, it happens seamlessly in 3 weeks or less.

Will my gas and electricity be interrupted if I switch?

Not at all. The way your gas and electricity supply comes into your home will not change. The same pipes and wires will be used and your meter remains the same. The only difference is you will now receive your energy bill from your new supplier.

Can I switch over the phone?

You can, but you’ll need to contact the energy companies individually to get their pricing. The comparison websites do not offer a comparison service over the phone, it’s an online only service.

Do I need to tell my current supplier?

No, you don’t. Your new supplier will take care of this. Your new supplier will inform your current supplier that you are switching, and they will handle the transfer. You should hear from your new supplier with a switching date after signing up.

Do I need to cancel my direct debit?

You do not. This is done automatically after your final bill payment (if applicable).

Can I switch gas and electricity if I owe money?

It depends. If you’ve been in debt with your current supplier for less than 28 days you can switch. That might be the smart choice because your energy bill will be lower and you can put the extra money towards paying off your old supplier. If you have owed the money for longer than 28 days you need to clear the outstanding balance before you can switch.

Can I switch energy supplier if I am on an economy 7 meter?

Yes. Most suppliers offer their own economy 7 tariffs, you can compare these on any energy comparison website.

Can I switch if I am on a prepayment meter?

Yes. Almost all the energy suppliers offer one or more prepayment tariffs just like other types of energy meters; some will save you more than others.  

Can I switch energy suppliers if I rent?

Check the terms of your tenancy agreement for clarification.  In most cases, if you are responsible for paying the utility bills at the property you rent you have the right to choose your own energy supplier. All good landlords will not refuse this unless they are paying the energy bill directly.

Can I switch energy supplier if I have a smart meter?

Yes, having a smart meter does not prevent you from being able to switch providers. While they will continue to work the smart meter will lose the ability to automatically send your usage to the supplier each month. You will have to log in and do this manually when needed. It’s a minor inconvenience for potentially significant savings on your bills!

Can I switch if I am in a new build home?

Yes, the building contractor will have set up an energy contract for the new build. If you are the first owner/occupier you can enquire who the energy supplier is if you haven’t yet seen a bill or wait for the first one to arrive. Once you have established who your supplier is you can start looking for a better deal.

Can I switch if I am on a standard variable tariff?

Yes, and the great news is for standard variable tariffs is there are no exit fees!

Can I switch gas only or electricity only?

It is possible to have one supplier for your gas and another supplier for your electricity. In most cases however, you get a better deal by signing up for a dual fuel tariff rather than splitting them.

Can I compare only renewable energy suppliers?

You can. When performing an energy comparison search, filter by green energy to identify only those suppliers who use 100% renewable energy sources.

Can I get cashback for using a comparison website?

Yes sometimes, when looking through your results you can filter by rewards. On most of the comparison sites, this will show you the tariffs which offer a switching incentive including cashback or vouchers. You will receive the cashback reward after your switch is complete. The details will be in your confirmation from the comparison website. You can also get cashback from Quidco and TopCashback for using certain comparison sites for your switch.

What does Martin Lewis say about energy comparison websites?

Martin Lewis has previously highlighted that energy comparison sites hide the cheapest tariffs. And many don’t automatically show consumers the best deals for them. He mentions that you must select the see all filter to view all results. He has also advised that people should switch tariffs regularly to take advantage of the best deals and save £100’s.

What is a unit rate?

This is the cost of energy per unit. Your unit rate will vary depending on your tariff, your payment method and where in the UK you are located.

What is a daily standing charge?

This is a daily charge that does not change. This is the minimum your supplier will charge each day for the energy supply. It covers the costs of supplying energy to your home and any maintenance and logistics to keep your connection going.

Is there a cooling-off period when switching?

Yes. Once you start the switch you enter a 14-day cooling-off period. During this time you can cancel or change your mind without penalty.

Do comparison websites offer any NHS discount?

Not as such. There are NHS discount websites such as which have links through to energy comparison websites. But it does not state that they benefit from any extra saving.

How do comparison websites compare to auto switching?

Auto Switching is an automated service you can sign up for. Every year or at the end of your contract it compares, chooses the most competitive tariff and switches you automatically. The benefit is you never get stuck on a standard tariff. By contrast, comparison sites give the consumer the option to search manually, compare and switch. The choice of which energy supplier to go with next is yours. Usually, the comparison website you used to switch will send you an automatic reminder listing the best available deals. You can then choose which one to switch to based on your preferences. Both can save you money, but auto-switching means you don’t have to do anything. However, you do have to trust the deal chosen is right for you.


Hi, I'm Rob and I run I initially started this project 5 years ago when I was looking to switch energy suppliers and found there wasn't a website that provided simple, data backed reviews on all the suppliers available. Since then, I spent have a lot of time (too much some may say!) looking at all publicly available data about each supplier and writing reviews using this information. These reviews are updated as regularly as possible and any data is backed up by a source where necessary. I have also started writing guides on various energy related topics which hopefully you will find useful. If you find any issues, please use our contact form to let us know.

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