How to measure a bay window

Bay windows add character to any room but measuring them for curtains and blinds requires a different approach. Follow our guide for perfect results:

Tools you'll need before you start
Steel tape measure (more accurate than a fabric one).
Pencil and paper.
In this guide
Measuring instructions
How to measure a large bay window
What are the differences when measuring a bay window
Common mistakes when measuring bay windows
Frequently asked questions

Measuring Instructions

For most homes, a track that follows the shape of your bay is the easiest option, and your measurements depend on whether you choose a track or a pole. Bay curtains need to travel around every angle or curve, so measure along the whole bay rather than straight across the front. Individual blinds sit in each section, with a little room to spare at the corners. Need help? Book a free online appointment or pop in store to find out more.

Step 1: Choose a bay track or a bay pole
Before you reach for the tape measure, decide what your curtains will hang from. It changes what you measure and where.
A curtain bay pole can look gorgeous and decorative, but it needs a little more thought. Standard support brackets can get in the way of your curtains. If you'd like them to glide right round the bay, you may need a specialist bay pole with passing rings and brackets, which are designed to let curtains move freely around corners and support joints.
Bendable tracks are also a great option as the track can be bent by hand, making it perfect for angled bay windows.

Step 2: Choose your curtain heading
Your heading style affects how much wiggle room you have when measuring.
Pencil pleat: The adjustable gather helps you get the perfect fit, which is handy because bay windows often need a bit of flexibility in the finished curtain width.
Pinch pleat: A smart, tailored choice that works well with tracks or specialist poles with rings. The finished heading is more structured, and the width is less adjustable, so accurate measuring is especially important.
Eyelet: These curtains suit some specialist bay poles but offer less flexibility. Support brackets and joints can stop eyelets travelling freely round the bay.

SHOP PENCIL PLEAT CURTAINS SHOP EYELET CURTAINS 

Step 3: Measuring a bay window for curtains
Take your time, take note of each measurement as you go, and measure twice.
Follow the full shape of the bay rather than running straight across the front. This is the path your curtains will take.
Measure the length of track or pole you need to follow every section of the bay, end to end, so your curtains can reach every angle. Check the instructions for your chosen track or pole for the exact allowances at each end.
When open, curtains should sit neatly at the outer edges of the bay. This lets in the most daylight and keeps your bay window space clear, so leave room at each end.
Decide where your track or pole will sit, then measure from there to where you'd like the curtains to finish. Ideally the heading sits high enough to hide the track, where the design allows.
Pencil pleat curtains with multiple hook-pocket rows let you fine-tune the finished hanging height.
When closed, your curtains should glide smoothly round the bay and meet comfortably, without strain.

Step 4: Measuring a bay window for blinds
Accurate measuring is especially important with blinds in a bay. Blinds usually fit each section individually, so measure every section on its own rather than treating the bay as one big opening. As you measure, leave room for anything that could clash at the corners including other blinds, headrails, brackets, window handles and fabric rolls. These allowances help your blinds work smoothly around the corners and angles of your bay. Skip them and blinds can catch on each other or on your window handles.
Roller blinds: These are neat and simple, and their slim design works well around angled corners. Each bay section can work independently, so you can control light and privacy exactly how you like.
Roman blinds: These give a soft, decorative finish. Fit individual Roman blinds to each section, with blackout and thermal lining options available.
Venetian blinds: These are brilliant for adjustable privacy. Tilt the slats to control light levels while still letting natural light in.
Perfect Fit® Pleated Blinds or Perfect Fit® Shutters: These are a great choice for uPVC windows and doors. They fit directly onto each window frame for a neat, snug finish, with no drilling or permanent fixings around the bay. Our Perfect Fit® Pleated Blinds also have a honeycomb cellular structure to boost insulation and keep your room comfortable all year round. Check out our measuring guide for blinds to find out more.

💡 TOP TIP
When choosing Roller, Roman or Venetian blinds for a bay window, make sure to think about if left and right chain control side is so you can operate the blind without any obstacles Check out our Perfect Fit product pages for further measuring advice and videos.​

Step 5: Measuring a bay window for curtains and blinds
Layering curtains and blinds is a popular way to dress a bay window. Fit individual blinds to each section for everyday privacy and light control, then add curtains around the bay for style, softness and extra insulation. Measure the blinds and the curtain track separately and plan your track position so it clears the blind headrails and brackets. Layering also means you don't need to open and close your curtains every day. Your blinds do the practical bit, while your curtains frame the window beautifully. And when you want extra privacy, warmth or light control.

SHOP CURTAINS  SHOP BLINDS 

How to measure a large bay window
Got a large bay window? It just needs a little more planning. If your window is tall, manual pull chains on Roller and Roman blinds can be hard to reach. For larger windows, consider a 6 inch pinch pleat rather than a 3 inch one, so the heading is nicely balanced with the window. Curtain tracks tend to run more smoothly than a curtain pole on larger windows, including bays. For a really wide bay, three or four curtain panels instead of one big pair makes curtains easier to open and cuts down on bulky stacking at the sides. Blackout curtain linings are perfect for big glazed areas, where heat loss and light control matter. For a traditional large bay, we recommend full-length pencil pleat curtains, a deep heading type and a shaped bay window track. You'll get great coverage, smooth operation and plenty of flexibility in the heading.

💡 TOP TIP
For a neat finish, make sure the heading sits high enough to hide the track where possible. Open curtains should gather neatly at either side of the bay, and closed curtains should glide round it without strain.

What are the differences when measuring a bay window 
In comparison to a standard window, a bay is made up of several sections set at angles, and whatever you choose has to work with every one of them. The differences between standard windows and bay windows are that curtains need to glide smoothly round the bends, and blinds need to sit side by side without clashing. Standard support brackets and joints can stop curtains travelling all the way round the bay and bay windows are usually bigger than standard windows, so they need more fabric and more components.

Common mistakes when measuring a bay window
Some common mistakes when measuring for bay windows include measuring straight across the front of the bay instead of along its shape. Choosing a pole with standard support brackets when you want curtains to travel all the way round. Forgetting that pinch pleat curtains have much less width adjustment than pencil pleat. Not leaving room for window handles, headrails and brackets when measuring blinds for neighbouring sections. Finally, fixing the track too low, so the heading doesn't hide it.
Made to Measure for bay windows
Our Made to Measure service is a brilliant way to get a bay window looking just right. Bay windows have lots of angles and sections, so standard sizes can leave you with gaps, overlaps or a fit that never quite sits right. With Made to Measure, your curtains or blinds are made to your exact measurements, so every section of your bay gets the right fit. Book your free online appointment or pop in store to find out more.

Frequently Asked Questions
Should I measure my bay window as one window or several?
For blinds, measure each section separately, as individual blinds fit each part of the bay. For curtains, measure along the full shape of your bay track or pole, as your curtains need to travel round every angle.
What's the best curtain type for a bay window?
We'd recommend pencil pleat or pinch pleat curtains. Pencil pleat is the most flexible and easy to adjust for width and height. Pinch pleat gives a more tailored look but needs more accurate measuring.
Should I choose a track or a pole for my bay window?
A track is the most practical choice because it follows the angles and curves of your bay with ease and suits pencil pleat curtains. A pole can be a stylish alternative if you choose a bay pole with passing rings and brackets.
How do I stop my blinds clashing at the corners?
It’s important to leave room for blinds, headrails, brackets, window handles and fabric when you measure, so your blinds can work smoothly around the angles of your bay.
Do I measure differently for Perfect Fit® blinds?
Perfect Fit® blinds and shutters fit directly onto each window frame, so you measure each frame individually. Follow the specific measuring guidance for your chosen product.
Need help measuring your bay window?
Book an online appointment or pop instore where we can book an in home measurement check by one of our experts, backed by our MeasureSafe Guarantee.