When To Lower Crib Mattress: A Simple, Safe-Use Guide for Parents

If you’re searching for “When To Lower Crib Mattress,” you’re usually trying to balance two things: keeping your baby safe while also making daily life (like lifting them in and out) manageable. This FAQ-style guide walks through the key signs, typical ages, and practical tips so you can adjust your crib mattress with confidence.

What Does It Mean To “Lower the Crib Mattress”?

Lowering the crib mattress means moving the mattress support to a lower height setting as your baby grows.

Most cribs have multiple levels:

The highest setting is used for newborns.
One or two middle settings are used as baby starts to roll and sit.
The lowest setting is used once baby can pull up or stand.

The goal is simple: keep the crib sides high enough that your baby cannot climb or fall out.

When To Lower Crib Mattress: What’s the General Timeline?

There is no single exact date that fits every baby, which is why developmental milestones matter more than age. That said, many parents follow this rough pattern:

Newborn to early rolling – mattress on the highest level
Rolling and beginning to sit – move to a middle level
Pulling to stand or cruising – mattress on the lowest level

Key Milestones to Watch For

You’ll usually want to lower the crib mattress when you notice these changes:

Your baby can roll both ways (back to tummy and tummy to back).
Your baby can sit up independently or is very close to it.
Your baby can pull up to a kneeling or standing position.
Your baby is tall enough that the crib rail looks lower on their chest than before.

Whenever you’re unsure about when to lower crib mattress, err on the side of caution and lower it a bit earlier rather than later.

How Many Times Should You Lower the Crib Mattress?

Most cribs are adjusted two or three times during your baby’s first couple of years. A common pattern looks like this:

Highest setting – birth to rolling regularly
Middle setting – rolling and sitting, but not yet pulling to stand
Lowest setting – as soon as they can pull up, stand, or are getting more active in the crib

If your crib only has two positions, you’ll likely keep it on the highest for the early months, then move it straight to the lowest once your baby becomes more mobile.

What Are the Safety Signs It’s Time To Lower the Crib Mattress?

Safety comes before convenience. As soon as your baby shows certain abilities, it’s time to adjust.

Clear signs to lower immediately

If you notice any of these, lower the mattress as soon as possible:

Your baby can sit up unassisted in the crib.
Your baby pulls up to kneeling or standing on the crib sides.
Your baby bounces while holding the rail.
The top of the crib rail is getting closer to their chest level when standing.

These are strong indicators that your baby could lean too far or attempt to climb.

Does Baby’s Age Matter When Deciding When To Lower Crib Mattress?

Age can be a general guide, but babies reach milestones at different times. Many parents find they start lowering the crib:

From the highest to a middle level: often around the time baby rolls and begins to sit, sometimes within the first several months.
From the middle to the lowest level: once baby pulls to stand, which often appears later in the first year or into the toddler stage.

Instead of focusing on a specific month, pay more attention to what your baby can physically do in the crib.

Practical Tips for Lowering Your Crib Mattress Safely

Check the crib manual for correct installation steps and weight limits.
Make sure all bolts and brackets are tight after adjusting the height.
After lowering, place your baby in the crib and visually confirm the rail is well above their chest when standing or pulling up.
Remove any thick toys, pillows, or bumpers that could be used as a step for climbing.
Re-check the crib regularly as your baby grows taller and more active.

❓ Common Follow-Up Questions About When To Lower Crib Mattress

Should I wait until my baby is standing to lower it?

No. By the time your baby is standing confidently, you may already be cutting it close. Lower as soon as your baby can pull up, even partially, or is trying to climb.

Is it okay to keep it higher for my own back?

While lifting from a higher level is easier, safety should come first. If your back is a concern, you can:

Bend your knees when lifting.
Move your body closer to the crib before you pick your baby up.

But still follow the safety signs on when to lower crib mattress.

When is the crib mattress at its final height?

The lowest setting is usually the final position and often stays that way until:

Your child is climbing or attempting to get out of the crib, or
Your child reaches the maximum height or age limit recommended for crib use.

At that point, many parents transition to a toddler bed or another sleep option.

✔️ Quick Mattress Takeaways

Key points parents should understand about When To Lower Crib Mattress

Focus on milestones, not months: Rolling, sitting, and pulling to stand matter more than age.
Lower in stages: Start high for newborns, then move to middle, then lowest as mobility increases.
Lower sooner rather than later: If you’re unsure, adjust down for extra safety.
Check height against your child: The crib rail should stay well above your baby’s chest when standing or pulling up.
Secure the crib every time you adjust: Tighten all hardware and keep the sleep space clear of climbable items.

By understanding when to lower crib mattress and watching your baby’s development closely, you can keep their sleep space both comfortable and safely adapted as they grow.