How To Lower Crib Mattress? Things Moms to Know.

From the day your baby is still tiny and sleeps safe in the crib, to the day he starts to flip over, crawling then climbing, things can change really quickly to adapt to his development. So, understanding what to do in each stage is never excessive for every parent. Here is our guide on how to lower crib mattress when your baby is getting older.

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Why do you need to lower your crib mattress?

The main reason for lowering your crib mattress lies in the safety of your baby, which is always the most important.

Young infants under 5 months old can sleep safely in the crib with the mattress at the highest position. However, when the babies start to sit up or stand up, and especially when they have learned to explore the crib more, like tiptoeing or climbing, it’s time to lower your crib mattress.

The mattress, at this point, should be lowered at the level that even when your baby is standing up, with his hands reaching up the rail, he can’t fall over.

Crib accidents account for 83.2% of baby injuries every year, so lowering the crib height at a suitable time is always crucial.

When to lower the crib mattress?

When to lower crib mattress

As we mentioned earlier, when your baby learns to sit up or stand up, it is the perfect time to lower the crib mattress.

It might not be necessary to set the crib mattress all the way down, which may be a bit inconvenient for you to bend over to take care of your baby.

You can find one particular level that even with two hands pulling up high, your baby can’t flip themselves over the rail, and eventually lower the crib as your baby grows.

A common suggestion for moms is when the baby is 36 inches tall, you should transfer them to the toddler bed.

But, in reality, there is actually no rule of thumb because of the variety of crib and crib rails heights available, also not every baby sits up or stands up at the same time.

So, you had better figure out what is best for your little one.

How to lower a crib mattress?


If you own a crib that has adjustable crib heights, lowering it should be simple with step-by-step guides from the manufacturer.

Step 1: Determine the mattress height

You will need to determine which level you want to set your mattress on. Based on the safety explanation above, you can check and find out what works best for your baby.

Depending on the crib you have that you can choose the mattress height level, usually, there will be four stages for a standard crib.

Step 2: Make the crib “empty”

Remove your sheets, mattress covers, or any type of bedding that you have. This step helps you to not bother with them while working with your crib.

Step 3: Unscrew the crib

Use a screwer or a drill to take out the back screws and then set the foot of the crib to the level you have decided from earlier first. Put back the screws then repeat the same process for the head of the crib.

You can also unscrew both the foot and the head at the same time, align your mattress, then reattach the screws.

Step 4: Test it again and lay back the sheet

Test your crib and put the sheets back on.

Just place any object that is heavier than your child onto the crib mattress to see if it can hold the weight, or if the crib slides down. You need to make sure you have reattached the screws tightly enough so this is one way to find out.

How far to lower the crib mattress?

In terms of how far you should lower your crib mattress, American Pediatric Association does give a recommendation that 26 inches from the crib rail to the top of its mattress is a safe distance for your infants.

But, in many cases, how far to set the crib mattress down will depend on the development stage of your child and the adjustable height levels of the crib.

A typical, standard crib usually has 4 mattress height options, but different cribs can have different numbers of height settings and different increments coming with them.

Usually, you don’t have to set your mattress all the way down right away but rather based on the current stage of your baby.

For example, the highest level is generally safe for infants under 4 months old, in which parents won’t have to bend over too low to take care of their baby. The other levels are for when your baby is getting older and starts to sit up or stand up.

Here are different height levels of crib mattress that match each stage of your baby’s development:

  • Highest setting: safe for newborn infants who haven’t been able to stand or crawl, usually when he is under 5 months of age.
  • Middle setting: this setting is the second under the highest and is suitable for babies more than 5 months old (around 5-8 months), who can now sit up, roll over, or crawl around.

There can be several middle settings in one crib, you just have to check yours and find out what suits best for your baby’s current stage.

  • Lowest setting: When your baby has reached 8 months old or has grown enough to stand up, climb or pull himself up on the rail, this is the safe level to help him not fall over.

Once your crib mattress has already hit its limit mattress height and your baby is 3 years of age or is 35 inches tall, it is highly advised to make a transfer to a toddler bed for safety.

Should you lower the crib mattress to the floor?

Many cribs allow you to lower the mattress all the way to the floor, especially when your baby has been able to climb.

This is definitely a safe and smart solution, but still a temporary one. Eventually, you will have to get ready for a shift to a toddler bed.

The bottom lines

We hope by now you have had a full understanding of not only how to lower a crib mattress but also when and where to set your mattress height to ensure the safety of your loved one. Share with us your concerns if you do have any. Happy parenting!

Read more:

How to Choose a Crib Mattress


Last Updated on May 7, 2021 by