Boilers aren’t something appealing.
No one brags about their new combi boiler. You don’t frame it on Instagram. You don’t talk about it at dinner parties.
But when it breaks?
Oh, now we’re paying attention.
If you’ve found yourself Googling ‘’how much does it cost to install a boiler’’ at 1 AM—while wrapped in three blankets, wearing two pairs of socks, sipping tea that’s gone cold—you’re not alone.
Boilers are one of those things we don’t think about until we have to. And then suddenly, we’re hit with quotes, brands, models, installation options… and none of it makes any sense. So, let’s sort it out.
We’ll break down everything you need to know—boiler installation costs, types of boilers, what you’ll really pay (unit + labour), and how to avoid getting rinsed in the process.
And if you’re going to drop two to four grand on heating your home, you deserve to know where every penny’s going. Let’s get into it.
How Much Does It Cost to Install a Boiler (Average Costs)
Alright, brass tacks time.
The average boiler installation costs in the UK typically fall somewhere between £1,800 and £4,000. Yes, that includes the boiler unit and the installation. But the range is wide. Here’s what usually rolls into the price:
- The boiler itself (that’s your hardware)
- Labour costs (we’ll get into this later)
- New pipework or tweaks to your existing setup
- A system flush (gets rid of the gunk in your radiators)
- Flue kit (you need one to vent gases safely)
- Controls (thermostats, timers, etc.)
- VAT (of course)
If you’re asking how much does it cost to install a new boiler in a standard two-bed flat with a like-for-like swap? Probably closer to £1,800–£2,200.
But if you’re upgrading your system, moving the boiler, or dealing with pipework that looks like it was installed during the Victorian era, expect numbers closer to £3,000–£4,000+.
Also—yes, some companies charge more for labour (not us, definitely!), and your location can also play a role in pricing, especially if you live in an area like Bristol.
Which Boiler Type Suits Your Home? Installation Costs Breakdown
Not all boilers have the same features or heating capability. And not all homes need the same setup.
Here’s where the price starts to move around depending on the type of boiler you go for.
Combi Boilers (Combination Boilers)
- Combi boiler installation costs: £1,800 – £3,500
Cheaper install, faster setup. Less to go wrong. Which is probably why it’s the most common type in the UK. Combi boilers heat water on demand and don’t need a separate hot water tank. Great for smaller homes or flats with one bathroom. Simple install = lower labour cost.
System Boilers
- Installation costs: £2,000 – £3,800
These need a hot water storage tank but no cold water tank. Perfect for homes with more than one bathroom. A little more complex to install than a combi, so you’ll feel that in the labour cost.
Conventional Boilers (Regular or Heat-Only Boilers)
- Cost of installing a new boiler: £2,200 – £4,000+
Old-school style. You’ll need both a hot and cold water tank. Often used in older homes or where the existing system matches this layout. Installation is the most complex. It takes time. And time costs money.
One thing to note: switching from one boiler type to another (say, from conventional to combi) usually racks up more cost. More pipework, more materials, more time is needed. So the final cost will increase as a result.
How Much a New Boiler Unit Cost in the UK
This is where things start to split.
Because when we talk about how much does it cost to install a boiler, what we’re really saying is—how much for the unit, and how much to fit the thing?
Let’s tackle the unit first.
Here’s a quick breakdown of average boiler unit costs in the UK (no installation yet):
- Budget Combi Boiler: £500 – £900
- Mid-Range Combi Boiler: £900 – £1,200
- Premium Combi Boiler: £1,200 – £2,500+
If you’re going for a system boiler, expect to pay slightly more for the unit—usually £1,000 – £2,000.
Heat-only boilers (also known as regular boilers) sit in the same ballpark: £900 – £1,800, depending on brand and output.
And here’s the bit people forget—sometimes the cheapest boiler ends up being the most expensive when you factor in running costs and boiler repairs two winters in.
You don’t need the fanciest model out there. But if your “deal” has a brand name no one’s heard of, back away slowly.
Boiler Installation Labour Costs Explained
Okay. So you’ve picked your boiler.
Now you’ve got to pay someone who actually knows (read Smart Plumbing & Heating!) what they’re doing to put it in.
Boiler installation labour costs in the UK usually range from £500 to £1,500, depending on:
- Type of boiler you choose for central heating & hot water.
- Whether it’s a straight swap or a full system change.
- Where it’s being installed (loft installs = extra faff = higher cost).
- Region (yes, it matters).
- Time of year (winter = plumbers are busier = you pay more).
A straight-up like-for-like boiler swap (same type, same location) can often be done in a day—and you’ll sit on the lower end of that range.
If you’re relocating the boiler, upgrading pipework, switching from conventional to combi, or doing anything else that adds complexity? It could take 2–3 days and push labour closer to £1,200+.
Keep in mind: a cheap quote isn’t always a smart quote. Ask for certification. Ask about warranties. Ask what’s included. Because no one wants surprise fees once the old boiler’s already in the skip.
Top Boiler Brands in the UK and Their Pricing
Let’s talk about brands.
Some names come with a solid reputation and solid support. Others are a mystery wrapped in a discount wrapped in regret.
Here are some of the best boiler brands in the UK right now (plus what you’ll likely pay for just the unit):
Worcester Bosch – £900 to £2,500
Tried, tested, reliable. Big fanbase. Great aftercare. Most gas engineers have worked with them before.
Vaillant – £850 to £2,300
German engineering, sleek design, strong performance. Usually, it’s a solid pick for system or combi boiler installation.
Ideal – £700 to £1,500
Bit more budget-friendly but still decent quality. Common in rental properties and small homes.
Baxi – £700 to £1,600
Another no-fuss, good-value boiler brand. UK-made, easy to service, parts readily available.
Viessmann – £1,000 to £2,000
A bit more premium. Energy efficient, modern, quiet. Great for those who like the finer things in life… including heat.
Remember: some brands bundle longer warranties into their prices. That might bump the upfront cost a bit, but it can seriously save you down the line.
Also, check if installation by a Gas Safe-certified engineer is required to keep your warranty valid. That’s a thing. Another big thing is choosing a certified fitter by the respective brand, which can enable you to get an extended warranty.
For instance, Smart Plumbing and Heating is an approved installer for all major boiler brands, so with our boiler fitting, you can get the maximum warranty the brand offers.
How Much It Costs to Replace a Boiler
Replacing a boiler sounds like a simple job.
Old one out. New one in. Done before lunch, right?
Well… not always.
The cost of replacing a gas boiler usually lands somewhere between £2,000 and £4,500. But the exact number depends on a few questions:
- Is it a like-for-like swap (same type, same location)?
- Are you changing the type of boiler (like swapping from a system boiler to a combi)?
- Does the pipework need upgrading?
- Is the flue still up to current standards?
- Are you relocating the boiler?
A basic combi-for-combi replacement will usually keep your bill at the lower end—around £1,800 to £2,500.
But changing systems or moving the boiler to a new room? That’s more parts, more labour, more time = higher costs.
And remember, unlike us, some installers throw in extras like a magnetic filter or smart thermostat as part of a package. Others… will charge you for the screws they used.
Always check what’s included in your quote before saying yes.
What Pushes Boiler Installation Costs Up? Key Factors Explained
So, why does your neighbour pay £1,900 for their boiler, while yours comes in at £3,600?
Here’s where things get messy—in a good way. These are the main factors that affect gas boiler installation costs:
1. Boiler Type
The boiler type you pick for your central heating and hot water system is a major factor that affects how much the boiler installation is going to cost.
- Combi = cheapest to install.
- System = middle of the road.
- Conventional = the “this-will-take-longer” one.
2. Boiler Size / Output
Bigger home, more bathrooms, higher water usage = bigger boiler. Bigger boiler = more money.
3. System Upgrade or Conversion
Swapping from conventional to combi? You’re not just changing the boiler—you’re changing the system. That means more materials and pipework are needed. And that means more hours of labour.
4. Relocation
Keeping the boiler where it is? Geat.
Moving it to the loft, the garage, or a different room? That’s a longer install and usually adds £300–£800+ to your bill.
5. Additional Work or Repairs
Old radiators, dodgy pipework, low pressure issues—these can sneak into your installation quote without you even realising.
6. Installer Rates & Location
It’s not a secret: prices vary depending on where you live. Cities like Bristol = higher labour costs. Rural areas might cost less, but availability can be patchy.
And if you go with a big national company? Expect to pay more than you would with a reputable local company of boiler fitters.
Final Thoughts
Buying and installing a new boiler isn’t exciting. It’s not fun or Instagrammable. No one’s going to come over and say, “Wow, that’s a gorgeous Vaillant you’ve got there.”
But it is one of the most important home decisions you’ll make. And it’s easy to get overwhelmed—especially when you start figuring out ‘’how much does it cost to install a boiler’’.
We hope this informative blog post will help you find the answer.
Here’s the takeaway:
✓ Know your home, know your needs.
✓ Don’t go straight for the cheapest quote.
✓ Check what’s included. Every last part.
✓ Ask questions. Even the “silly” ones.
And whatever you do—make sure your installer is Gas Safe registered. No exceptions.
Because no one wants to spend three grand only to end up cold and confused.
