5 things I wish I knew before buying an electric heater

I’ll be the first to admit that I’m very frugal when it comes to energy use in my home. Energy prices are no joke, after all. That’s why I try to avoid turning my heating on for as long as possible, opting for electric heaters to ‘heat the human, not the home’ instead. But there are many things I wish I knew before buying an electric heater.

Of course, you probably don’t need me to tell you that the best electric heaters are a must-have for the colder months of the year. But the reality is that there’s a lot of noise around electric heaters, from confusing information around the different types of electric heaters to the costs to buy and run them. As a result, I’ve bought a lot of heaters over the years, many of which weren’t quite right.

Through this trial and error, I’ve finally been able to find what works for me and my home, and now I couldn’t imagine winters without my electric heaters. However, I don’t want anyone else to waste as much money as I have over the years, which is why I’m sharing the 5 things I wish someone had told me before buying my first one.

1. Size does matter, but not in the way you’d think

To avoid making any electric heater buying mistakes, it’s always important to choose a heater that suits the size of your home. So, if you have a smaller and more compact space, it’s well worth choosing an electric heater that’s smaller in size. But the size of an electric heater doesn’t always correlate to the power of the appliance, so you don’t necessarily need to go bigger if you have a bigger house.

Instead, one thing I think everyone should know before buying an electric heater is that the wattage is the most important factor. This is its power output, which is ultimately how much heat it can produce. The higher the wattage, the more impressive the heat output, and electric heaters typically range from between 500-2500W.

And while bigger appliances often have the means to offer a higher wattage, that isn’t a hard and fast rule. This is good news for those with a smaller house, as this means that you don’t necessarily need to buy as many electric heaters to heat your home. Instead, you can opt for a smaller appliance with a higher output.

For example, I’m currently testing the Dreo Smart Whole Room Heater 714S, £99 at Amazon, and it really does offer the best of both worlds. It’s small enough to sit on my desk while I’m working or on the coffee table in my living room, but it’s also powerful enough to heat the entire room. This is all thanks to its 2000W of power.

2. Some are *very* loud

Although I know that you shouldn’t leave an electric heater on overnight, I still didn’t really consider the noise when buying my first one. And while I may not use them while I’m sleeping, I still use them when I’m working from home, having virtual work meetings, and trying to watch TV. And some electric heaters are very loud.

In my experience, the loudest electric heaters are undoubtedly fan heaters, as they use a fan to blow hot air around the room. And while I personally use the Dyson Purifier Hot+Cool HP1 Purifying Fan Heater the most in my house, I have to be careful about when I use it so it doesn’t distract me. That’s because this electric heater runs at around 63 Decibels, which is the same noise level as a normal conversation.

If background noise is an issue for you and you’d prefer something silent, it’s best to opt for a convector, ceramic or one of the best oil-filled radiators. These have fewer moving parts, so they tend to be a lot quieter. In fact, I also have the AENO Premium Eco Smart Panel Heater in my house. And while it takes a lot longer to heat up than a fan heater and is significantly bigger, it’s the option I choose when I have a meeting or want to pay closer attention to the music I’m listening to or the film I’m watching.

That’s not to say that all fan heaters are loud, though. The Dreo Space Heater is one of the quietest fan heaters we’ve tested, coming in at around 37.5dB or around 40dB when it’s in oscillation mode. This is comparable to a quiet library, so it is much easier to cope with. So, this is something to consider if noise is a make-or-break feature for you.

3. Running costs really do vary

One thing I didn’t realise until recently is that, when it comes to whole-home heating, central heating is always going to be cheaper than using an electric heater. But I know from my own experience of having spare rooms that I don’t use that there’s often no need to waste energy heating an entire house.

That’s where electric heaters reign supreme, as they allow you to heat individual people and rooms, ultimately making the process cheaper in the long run. However, the cost to run an electric heater still varies more than most people think, which is why everyone should know how much the electric heater they have their eye on costs if they want to save energy at home.

To work out how much it costs to run an electric heater, all you need to do is take the kW of the heater (this is the wattage divided by 1,000) and multiply it by the current price of electricity. For example, to calculate the cost to run a 1.5kW (1500W) heater in the UK and under the current October 2025 price cap, you’d multiply it by 26.35 pence per kWh.

This means that the average 1500W electric heater will cost you about 40p per hour to run. But even then, there are some factors that determine which is the cheapest electric heater to run, like the type of heater and where you place it. So, always take this number with a pinch of salt and buy a smart plug – like this Tapo P110 Smart Wi-Fi Plug (£9.99 at Argos) – if you want to get an accurate depiction of how much it’ll actually cost you.

4. It isn’t a miracle worker

As someone who has bought multiple electric heaters, I could rave about them until the cows come home. They’ve helped me heat my home without turning the heating on, and I genuinely couldn’t comfortably live in my home during the colder months without them. However, one thing I wish I knew before buying an electric heater is that they’re not miracle workers.

Ultimately, an electric heater will only ever be effective if you have the right home for one – i.e. one that is well-insulated and will retain the heat produced by the electric heater. If you have a draughty house with very poor insulation, you’re only going to get temporary satisfaction out of your electric heater, as the heat will simply leak out of your home.

Because of this, there’s very little point in buying an electric heater until you’ve addressed the problems with your home. It might be that simple DIY draught-proofing, like using this Weather Stripping Tape, £9.99 at Amazon, to block gaps in your doors and windows, will be enough. In more extreme cases, you may need to completely reassess your insulation.

Only when your home is in better shape can you really reap the rewards of an electric heater, so it’s important to keep your expectations in check if you have an older property. This is something I’ve had to address in my damp-prone Victorian house, and I’ve found that my electric heaters are way more effective since I addressed the draughts coming from my wonky walls, windows, and doors.

5. Smart features come in very handy

Although I’m a millennial who grew up with technology, I must admit that I don’t particularly like having a lot of smart tech in my life. I try to keep my phone as app-free as possible, I prefer old-school thermostats to smart ones, and I’ve yet to buy an Alexa or Google Assistant.

But one thing I wish I knew before buying more basic electric heaters in the past is that smart features can come in very handy when you want to keep a home warm in winter. In fact, the only apps I really have on my phone are the ones that control the electric heaters that I have in my house.

That’s because these smart features allow me to have better control over the heating of my home – and, ultimately, how much I’m spending on my energy bills. In fact, many electric heaters come with built-in thermostats, which means it’ll automatically switch off as soon as it reaches your desired temperature, so you’re not wasting any energy.

Being able to set schedules also allows me to turn my electric heaters on from my phone, without even needing to be in the house. This comes in handy when I leave my WFH setup to go into the office. I turn my heater on before I get home so I don’t have to return to a freezing cold house, and the same can be said when I take the dog for a walk. So, if you value convenience, I wouldn’t scoff at a slightly more expensive electric heater that comes with these extra smart features.

My top-rated electric heaters

So, there you have it! Those are the things I wish I knew before buying an electric heater, so hopefully you won’t make the same mistakes I did.