Choosing the right box spring is not just about dependability or build quality. You also have to account for dimensions and how the box spring fits with the rest of the setup.
Otherwise, you can have a situation on your hands where the box spring doesn’t fit in the frame.
If a box spring doesn’t fit in the frame, it is likely due to the frame being wide. To fix this issue, set the box spring in place and measure the gap between it and the frame. With these measurements, cut plywood and place them in the gap. This will help stabilize the box spring.
It’s normal for this to occur as bed frames come in all shapes and sizes.
You have to be diligent and adjust based on how big the gap is between a box spring and the bed frame.
By using plywood, you can make sure the box spring does not budge once it’s set.
This guide will explain more on what to do if the box spring doesn’t fit in the frame.
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Steps To Follow If Box Spring Doesn’t Fit In The Frame
1. Place Box Spring In The Frame
Before using a bed frame gap filler, it’s important to know how the setup looks with the existing dimensions.
Each scenario is different when it comes to the gap’s size.
A smaller gap is going to be treated differently than a larger gap. Keep this in mind when placing the box spring in the bed frame at home.
You will immediately know if the bed frame is too wide for the box spring. Pay attention to this and take a picture to make sure you are aware of how it looks before working on filling the gap.

2. Measure Gap Between Box Spring & Bed Frame
You are now going to measure the gap between the bed frame and the box spring.
This is between the end of the box spring and the bed frame’s walls.
Take these measurements multiple times to ensure you have it right. It is best to make sure you are not rounding up or down. It should be an exact fit for the bed to look the way you want it to.
Mistakes here might make the bed seem uneven when the mattress goes on top.
If the box spring is too big for the frame, you will have to buy a new box spring. However, when the box spring is too small for the frame, you can take these measurements to work on filling the gap.
3. Cut Plywood To Fit The Gap
Now it is time to fill the gap.
What are you going to use for the job at hand?
It’s recommended to use a sturdy material such as plywood. This will help create a strong base for the box spring and mattress. You can wedge the plywood into the gap and make sure the box spring doesn’t slide.
Cut the plywood based on the measurements you took.
Once ready, place the plywood into the gap and ensure it does not budge.

4. Place Box Spring In Again To Test New Dimensions
The last step is to test the new setup.
You will want to take the box spring and put it back into the newly customized bed frame. Take your time during this process and ensure the box spring works the way it is supposed to.
When figuring out how a box spring should fit a bed frame, the first detail is to ensure it doesn’t slide, When a box spring slides, it becomes unstable and not an ideal surface for the mattress.
Be aware of this when setting things into place.
Can You Put A Box Spring On Any Bed Frame?
You cannot put a box spring on any bed frame. Some box springs are too big or too small for specific bed frames making them incompatible without customized changes. It’s important to consider sizing when choosing the right combination.
Final Thoughts
These are the tips to consider if a box spring doesn’t fit in the frame.
If a box spring doesn’t fit in the frame, it’s because the frame is too large. To fix this issue, place the box spring into the frame, measure the gap, and cut plywood to fill that gap. This will ensure the box spring is a perfect fit and doesn’t budge.
If you want to get things right, these are the details that matter most.
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