How Far Should Curtains Extend Past a Bay Window?

A simple guide to how far curtains should extend onto the walls outside your bay window.

When a bay window curtain track returns out of the bay, one of the most common questions is how far the track should continue onto the side walls.

It is easy to underestimate this. Many people ask for returns that are too short, while others worry they need very wide returns to get the curtains completely away from the bay.

In most cases, the best answer is somewhere in the middle.

Quick Answer

For most bay windows, your curtain track should extend around 20cm to 30cm onto each return wall, plus any extra needed to get past the end of the window sill.

If your bay has sill ends facing into the room, measure past the sill first, then allow around 20cm to 30cm of clear wall for the curtain return.

This is usually enough to let the curtains stack neatly, reduce side gaps, and give the track a proper flat section for wall fixing.

Why Very Short Returns Are Often a Problem

I often get asked for returns of around 10cm or 12cm. On paper, that can sound enough, especially if the customer only wants the track to come just outside the bay.

The problem is that the curtain track may still be curving out of the bay at that point.

If the return bracket is wall fixed, the track needs a nice flat section where the bracket connects to it. You cannot properly connect a wall bracket to a section of track that is still curving around the corner.

This is one of the reasons I usually recommend allowing at least 20cm of return wall after the track has come out of the bay.

Remember to Allow for the End of the Window Sill

If your bay window sill sticks out at the sides, you need to allow for this before measuring the return wall section.

For example, if the end of your sill projects 12cm into the room, you would normally allow that 12cm first, then add around 20cm to 30cm of wall return.

This allows the curtains to wrap around the end of the sill instead of stopping too soon and leaving a gap down the outside edge.

Curtain track returns extending past bay window

The Ideal Return Size for Most Bay Windows

For around 95% of bay windows, returns of around 20cm to 30cm plus any sill ends are perfectly adequate.

This gives a good balance between practical curtain stacking, neat side coverage, and a natural-looking finish.

The aim is not usually to pull the whole curtain completely out of the bay. In most cases, the best look is when around two thirds to three quarters of the curtain stacks on the return section, with the rest sitting just inside the bay.

This keeps the curtains clear of most of the side windows while still making the bay look dressed and balanced.

Why Wider Returns Are Not Always Better

Some people go the other way and ask for very wide returns, sometimes 50cm, 60cm, or even 70cm on each side.

They are usually trying to make sure the curtains stack completely away from the bay side windows. That sounds sensible, but in most rooms it is more than you need.

If the returns are too wide, the curtains can end up stacking right into the corners of the room. To me, this can make the whole layout look a bit odd and disconnected from the bay window.

It also means the track is longer, so you may need wider curtains to properly cover the full track when closed.

What About Blackout Curtains?

If you are hanging blackout curtains, slightly wider returns can help reduce light coming in at the sides.

Even then, I would usually only recommend around 30cm to 40cm returns, plus any sill ends.

That is normally enough to give better side coverage without making the curtains feel as though they are being dragged too far away from the bay.

The Rare Exception: A Full Wall of Curtains

Very occasionally, a customer wants the whole end of the room, including the bay window, to become one complete wall of curtains when closed.

This can work well if the return walls are fairly short, for example around 50cm each side, and the room suits a more dramatic curtain look.

But even with this style, you would not normally draw the curtains open as far as they can physically go. If you pull them right back into the room corners, you can expose the inside edges of the bay, which often does not look right.

A better finish is usually to leave the curtains covering the return walls and sitting slightly into the bay on each side. This keeps the bay dressed, even when the curtains are open.

Curtains stacked on return walls outside bay window

Lee’s Advice

For most bay windows, I would not go too short or too wide with the returns.

Short returns can cause practical problems because the track may still be curving and there may not be enough flat track for the wall bracket.

Very wide returns can make the curtains stack too far away from the bay and may mean you need wider curtains than necessary.

As a general guide, aim for 20cm to 30cm onto each return wall, plus any sill ends. For blackout curtains, around 30cm to 40cm can work well.

The best finish is usually when most of the curtain stacks on the return section, but a little still sits within the bay. That gives a softer, more natural look.

Still Not Sure How Far Your Track Should Return?

If you are unsure, start by looking at three things: the width of your sill ends, the clear wall space outside the bay, and where you want the curtains to sit when open.

You do not usually need huge returns. You just need enough room for the track to come out of the bay, sit flat on the wall, and let the curtains stack neatly.

Use the Curtain Track Finder See Bay Window Curtain Tracks

Frequently asked questions

1How far should curtains extend past a bay window?

For most bay windows, the curtain track should extend around 20cm to 30cm onto each return wall, plus any extra needed to clear the end of the window sill.

This gives enough room for the curtains to stack neatly without making the returns look too wide or out of proportion.

2Is 10cm enough for a bay window curtain track return?

Usually, no.

A 10cm return is often too short because the track may still be curving out of the bay. If the return is wall fixed, the bracket needs to connect to a flat section of track, not a curved section.

3Do I include the window sill when measuring the return?

Yes. If the end of your sill sticks out into the room, allow for that first, then add your return wall measurement.

For example, if the sill end is 12cm deep, you would normally measure past that 12cm first, then add around 20cm to 30cm onto the wall.

4Should the whole curtain stack on the return wall?

Not usually.

For most bay windows, the best look is when around two thirds to three quarters of the curtain stacks on the return section, with the rest sitting just inside the bay.

This keeps the side windows clearer while still making the bay look naturally dressed.

5Are wider returns better for blackout curtains?

Slightly wider returns can help with blackout curtains because they reduce light gaps at the sides.

For blackout curtains, I would usually suggest around 30cm to 40cm returns, plus any sill ends. In most rooms, you do not need returns wider than this.

6Can bay window track returns be too wide?

Yes. Very wide returns can make the curtains stack too far into the room corners, which can look unbalanced.

They also increase the overall track width, which may mean you need wider curtains to cover the track properly when closed.