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When to Lower Crib Mattress: The Complete Guide

The best time to lower your crib mattress is when your baby begins sitting up, when they start to pull up, when you are after the crib safety, and when your baby is above 35 inches. You must adjust the crib mattress height according to your child’s growth and development or whenever your little one hits a milestone.

As your baby grows, there comes a time when you need to adjust the crib mattress height to ensure their safety and comfort. Lowering the crib mattress is an important step in your child’s development and plays a crucial role in preventing accidents and promoting healthy sleep.

In this article, we will guide you through the process of determining when to lower the crib mattress and provide valuable insights to help you make an informed decision.

Table of Contents

When Should I Need to Lower My Crib?

The best time to lower your crib mattress depends on your baby’s growth and development. Every time the baby moves to the next stage, you will have to reduce the crib height accordingly to increase safety.

Also, remember you should check your instruction manual to know whether your crib mattress is adjustable before you begin setting. Here are different settings and when to apply them on your crib mattress.

crib mattress height

Highest Crib Setting

The highest crib setting is an excellent option for newborns that are immobile. It is the first setting that you can use when you move your baby to the crib.

The highest crib setting is also the easiest crib height you can opt for your newborn baby. The setting can accommodate babies under five months old.

Middle Setting

The middle setting also depends on your bundle of joy’s growth and development. Since your baby learns to sit independently at approximately 5 to 8 months, you must adjust your crib to the middle setting.

If you let the mattress remain too high, it increases the risk of your baby falling out since they are now in a position to sit on their own.

Lowest Setting

Here, you lower your crib mattress before the baby can make the next move of standing on their own. Ensure you reduce the bed to its lowest setting. You will notice most babies usually begin to stand on their own between 8 and 10 months.

They may also begin to show signs of climbing, and you must take more precautions to prevent your toddler from falling out of the crib. You can move them into a toddler bed if you notice they are showing interest in climbing.

When to Lower Crib to the Floor?

The appropriate time to lower the crib to the floor is when your little one starts climbing out of the crib. You need to understand that at this stage, your baby’s muscles are growing, meaning they can find their way out of the crib, which can be risky.

Also, if your baby is taller than 35 inches, you will have to lower the crib to the floor. If you notice they still climb and it tends to create a safety hazard, then you will have to move your little one to a toddler bed.

Step-by-Step Guide to Lowering a Crib Mattress

Let’s now walk through the step-by-step process of lowering a crib mattress:

Step 1: Remove the Bedding and Toys

Before making any adjustments, remove all bedding, Pad, toys and other items from the crib. This ensures a clean and safe environment for your baby.

Step 2: Adjust the Mattress Support

Most cribs have a mechanism to adjust the mattress height. Locate this mechanism and follow the manufacturer’s instructions to lower the mattress support to the desired level.

Step 3: Secure the Mattress at the Lower Level

Once the mattress support is at the desired height, secure the mattress in place using the provided hardware or mechanisms. This ensures that the mattress remains stable and doesn’t shift or wobble.

Step 4: Double-Check for Stability

Give the crib a gentle shake to ensure that it is stable and secure. If you notice any wobbling or instability, recheck the mattress support and make necessary adjustments.

Step 5: Reassemble the Crib

After confirming the stability of the mattress, reassemble the crib by putting back the bedding and toys. Ensure that everything is securely in place and there are no loose parts.

When to Transition from Crib Mattress to Toddler Bed

You can transition from crib to toddler bed when:

The Baby Can Climb from the Crib

If you notice your little one can now climb out of the crib on their own, it is a sign that you need to transition from the crib to a toddler bed. According to the American Academy of Pediatrics, you can transition when your baby is 35 inches tall.

It is because, at that height, they have grown big enough to try escaping from the crib. They can even climb out of the crib if the mattress is in the lowest setting. That can be dangerous since they might fall while escaping.

You are Excising Potty Training

It is vital to note that a crib and potty training do not go hand in hand since you want your bundle of joy to access the bathroom quickly. You can efficiently perform potty training using a toddler bed so your child can quickly relieve themselves.

The Child no Longer Fit the Crib

When your child can easily access both ends of the crib by the feet and head, you have to transition them to a toddler bed.

You are Getting Another Baby

You can upgrade your child to a toddler bed if they are at least 18 months old. However, you can transition your child to a toddler bed if you are expecting another baby. Ensure you are careful not to give your child the impression that they are about to be replaced by another. You can upgrade them one to two months before your newborn baby arrives.

Remember to make it exciting so that they do not feel left out. You can tell them they are about to get the big brother or sister with their big kid bed.

Useful Tips When to Transition from Crib Mattress to Toddler Bed

Upgrading your little one from a crib mattress to a toddler’s bed can be challenging; however, Here are tips and tricks you can maximize when you are transitioning your child from a crib mattress to a toddler bed:

  • Consider the Bed: You must get a mattress lower to the floor to avoid fallouts, especially if your baby is an active sleeper.
  • Encourage Your Toddler Bed Nap Times: You can encourage your child to sleep in the new bed so that they know this is where they need to sleep.
  • Keep Your Routine Consistent: If your child sleeps at precisely 8 pm, you must keep it consistent even on their new toddler bed. If you create any changes, it may cause unsettling for your child.
  • Let the Transition Be Exciting: You can get your toddler excited by the new bed by talking frequently about it using animation. Tell them how fun it will be sleeping on a “grown-up bed.”
  • Allow the Toddler to Get their Favorites: Since you want their new bed to be exciting and welcoming, you can allow them to pick their favorite stuffed animals, which makes them feel safe. Allow them to choose their favorite stuffed animals and pictures to stay in bed with them.
  • Be Patient: Do not be discouraged if their sleeping habit becomes a struggle for a while after transitioning to a toddler bed. You can expect a 2 to 3-week upgrading process.

Frequently Asked Questions

Can I use crib bumpers after lowering the mattress?

No, it is recommended to remove crib bumpers entirely to reduce the risk of suffocation or entanglement.

What if my baby can climb out of the crib even after lowering the mattress?

If your baby shows signs of climbing out, it may be time to transition to a toddler bed for their safety.

Is there an ideal age to lower the crib mattress?

The ideal time to lower the crib mattress depends on your baby’s individual development. Watch for signs of increased mobility and readiness, such as rolling over or attempting to climb.

Can I use a foam mattress instead of a spring mattress?

Yes, you can use a foam mattress as long as it meets safety standards and provides a firm sleeping surface for your baby.

Should I lower the mattress to the lowest position right away?

Lowering the mattress gradually or based on your baby’s developmental milestones can help them adjust more comfortably to the new height.

How often should I check the crib mattress height?

It’s a good practice to check the crib mattress height every few months or whenever you notice signs of your baby’s increased mobility. Regular checks ensure that the mattress is at the appropriate height for their current stage of development.

What should I do if my crib doesn't have adjustable mattress heights?

If your crib doesn’t have adjustable mattress heights, consider transitioning to a crib that offers this feature. Alternatively, you can place the crib mattress on the floor when your baby reaches the appropriate age and size.

Can I use additional padding to lower the crib mattress?

No, it is not recommended to use additional padding to lower the crib mattress. Adding extra padding can create a suffocation hazard and increase the risk of Sudden Infant Death Syndrome (SIDS).

What should I do if my baby keeps climbing out of the crib even after lowering the mattress?

If your baby is consistently climbing out of the crib, it may be time to transition them to a toddler bed for their safety.

Should I adjust the crib mattress height based on my baby's age or weight?

It’s best to follow the manufacturer’s guidelines for adjusting the crib mattress height, which usually consider both age and weight.

Can I lower only one side of the crib mattress for easier access?

No, it is important to lower the entire crib mattress to maintain its stability and prevent accidents.

How often should I check the crib for any loose or broken parts?

Regularly inspect the crib for loose or broken parts, at least once a month, to ensure your baby’s safety.


Lowering your crib mattress helps prevent your little one from getting injured by falling. The best time to reduce your crib mattress is when your baby begins sitting up, when they start to pull up, when you are after the crib safety, and when your baby is 35 inches and above.

There are a variety of settings you can use for your crib mattress, depending on the growth and development of your child. This setting includes the highest crib setting, middle crib setting, and lowest crib setting. You can follow the step-by-step guide in this article to lower your crib mattress successfully.

Author: Jessica

Jessica is a lover of both life and gardening. She loves to share his passion for both on social media. He often posts about his latest gardening projects, as well as tips and tricks for others who might be interested in starting their own gardens. She also frequently posts about the different aspects of his life that he enjoys, from spending time with friends and family to exploring new places.

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