The benefits of a window replacement are very clear, such as experiencing a reduction in energy bills, enjoying a new aesthetic and upgrading your security.
However, the cost is often far less obvious, because after all, windows aren’t exactly something you purchase on a regular basis. The price is dependent on a fair few factors, including the style and material you choose, as well as the size of the installation and the glazing type.
Because of these differences, the best way to understand the cost of replacement windows UK is to get a free no-obligation quote, which all reputable local installers offer. You can get one from ourselves right here.
As we said, final prices vary significantly, but for a budget-friendly uPVC casement window, prices typically start from around £500, and you can expect to pay into the thousands for a new bay & bow window, for example. We’ll outline expected costs in more detail below.

Cost of replacement windows UK
The prices below are typical starting figures for the UK’s most popular window styles.
All prices assume uPVC frames, a low-maintenance, thermally efficient material that is the most common across the UK. You may think that because uPVC is cheaper, it is low quality, which isn’t the case – uPVC can be mass-produced, unlike timber for instance, which naturally brings the price down. It’s actually a great choice for durability and energy efficiency.
Aluminium window frames are also available and tend to cost around 25% more, offering a sleeker, more premium finish with slimmer frames.
Prices sourced from Checkatrade and are intended as a guide only.
Casement windows
The most common window style in UK homes, can be operated using a simple handle. You can choose whether your casement windows open inwards or outwards.
- Great for ventilation, easy to operate
- Suits a wide range of property types
- The most cost-effective window style available
Estimated cost (supply and installation): £500-£750 per window for supply and installation. A full replacement for a typical three-bedroom house averages around £7,500.

Flush sash windows
Similar to a casement but with the sash (the openable part of the window), sitting completely flush with the outer frame, creating a smooth finish.
- A premium look that suits both modern and traditional homes
- Perfect for conservation areas and period properties
- All the low-maintenance benefits of uPVC with the charm of timber joinery
Estimated cost (supply and installation): From around £600-£800 per window.

Sliding sash windows
Two panels slide vertically past one another, a familiar and much-loved sight on Victorian and Georgian properties.
- Beautiful heritage character that suits period homes
- Smart natural ventilation design
- Available in uPVC for a maintenance-free finish
Estimated cost (supply and installation): £800-£1,200 per window.

Bay & bow windows
Projecting outward from your home’s exterior, bay and bow windows are a stunning architectural feature.
- Flood a room with natural light
- Create a charming window seat or extra interior space
- A real boost to kerb appeal and property value
- Cost more because additional structural work is often required
Estimated cost (supply and installation): £1,250-£2,150

Tilt & turn windows
A smart, modern window that tilts inward for ventilation or swings fully, making it easy to clean. Great for high-rises or homes with young children.
- Easy to clean from inside, ideal for upper floors
- Excellent security features and weatherproofing
- Thermal performance as good as the rest of our styles
Estimated cost (supply and installation): £590-£795 per window.

Window cost comparison table
| Window style | Estimated average cost (uPVC, supply & install) |
| Casement window | £500-£750 |
| Flush sash window | £600-£800 |
| Sliding sash window | £800-£1,200 |
| Tilt & turn window | £590-£795 |
| Bay & bow window | £1,250-£2,150 |
Aluminium windows typically cost around 25% more. Prices sourced from Checkatrade.
What impacts the cost of new window installation?
Frame material
uPVC windows are the most affordable option, and the most popular in every corner of the UK as a result. uPVC is a synthetic material, and is also used for doors and guttering. It’s incredibly strong, very easy to clean, and offers very competitive thermal performance.
Aluminium carries a higher upfront cost but offers slim, elegant profiles and exceptional durability for a truly premium finish.
Window style
The style of window makes a big difference to the final price. A standard casement window will always be more affordable than a bay window or sliding sash, due to the complexity of manufacturing and fitting them.
Number of windows
The more windows you replace, the higher the overall cost, though replacing several at once is often more cost-effective, as labour costs are spread across the installation.
Glazing type
Most new windows come with double glazing as standard, two panes of glass that trap warm air and reduce heat loss. Triple glazing adds a third pane, but this comes at an extra cost.
Added extras
A few finishing touches can add to your final price:
- Coloured or wood-effect finishes, a step up from standard white uPVC
- Trickle vents, small ventilation slots that help prevent condensation
- Decorative glazing bars, popular in period properties and conservation areas
- Upgraded hardware and handles

Why trust Northwich Glass for replacement windows?
The best way to find out exactly what your new windows will cost is to get a free, no-obligation quote from us. This can be done however you prefer, whether that’s with a phone call, via email, or by filling out our simple online form. These quotes cover everything from initial supply to the final installation and aftercare.
We offer a comprehensive range of uPVC and aluminium windows, including casement, flush sash, sliding sash, bay & bow and tilt & turn styles, in a wide choice of colours, finishes and hardware options.
Our windows are manufactured using premium materials from trusted suppliers including Rehau, Kommerling and the Residence Collection, so you can be confident in the quality of your investment.
We’ve been helping homeowners across Cheshire since 1959, and here’s what sets us apart:
- FENSA accredited: All installations meet and exceed strict building regulations
- Which? Trusted Trader: Independently verified for your peace of mind
- 10-year warranty on all installations as standard
- No-pressure sales, we’re here to help, not to rush you
You’re also welcome to visit our showroom at Leicester Street, Northwich, Cheshire, CW9 5HW, where you can see our full range up close and explore colours and styles in your own time.
Ready to get an accurate price? Call us on 01606 810 000, email reception@northwichglass.co.uk or use our online enquiry form to request your free, no-obligation quote today.
FAQs
Is professional installation required?
Yes! Whilst it can be tempting to install your new windows by yourself, it’s a risky move. With professional installation through reputable window fitters, the new glazing will be as thermally efficient as possible, making sure the seals are tightly secured for lower energy bills and no water ingress, whilst also making the space more comfortable. As well as better energy efficiency, correct fitting will also ensure your windows are more secure and will last longer.
What are the key factors in the cost of new windows?
Window prices depend on a huge range of factors, which makes it hard to give truly accurate quotes each time. Factors such as your chosen style, material, glazing, and even the area you live in will impact how much you pay. Our installations are completely bespoke, making it possible to find a good option for your budget and unique priorities.
What is included in the quoted price for window replacement in the UK?
Our quotes include both supply and installation of your chosen window style. You don’t need to worry about hidden costs. Quotes that seem too good to be true may come with unwelcome surprises at a later date.
