Baby lies in crib to showcase how to choose a baby mattress

For some parents-to-be, nine-ish months of pregnancy can feel a little abstract. Yes, there are doctor’s appointments, birth prep classes and a burgeoning belly, but it’s still hard to imagine how life will be when your new bundle of joy arrives. And then you buy a crib and it all becomes so much more real.

An important part of that purchase is the crib mattress, and there will be endless options to consider. But how do you choose a baby mattress that’s safe and comfortable? Read on for the answers to commonly asked questions and put your mind at ease.

And if you’re ready to dive right in, our best crib mattresses are right this way.

Questions to ask when buying a crib mattress

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1What are the Canadian crib mattress safety guidelines?

According to Health Canada, there are a few important boxes to check when choosing and using a baby mattress:[1]

Diagram detailing Canadian crib mattress safety guidelines

  • Firmness: Some safe sleep experts say that if a baby mattress feels like something you’d want to sleep on, it’s too soft for your little one.[2] Mattresses that are too soft or worn down may pose a safety risk, as they are more likely to create a gap where the baby’s face could get stuck, making it difficult to breathe.
  • Thickness: Baby mattresses should be no thicker than six inches (15 centimetres) and must fit tightly within the crib’s frame.
  • Gaps: There must not be a gap of more than 1 3/16 inches (three centimetres) between the mattress and any part of the crib’s sides.[3] Push the mattress into each corner to check for gaps.
  • Support: Before using the crib, check the crib’s mattress support (the adjustable platform that holds the mattress in the crib) to ensure it is secure. You can do this by shaking the crib, thumping the mattress and pressing on the mattress support from the bottom to ensure the mattress stays in place.[4] Test it often once your new addition arrives.
  • Manufacturer guidelines: If a crib comes with a mattress, only use that mattress.[3]
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Safety Tip
No matter which mattress you choose, your baby is safest when they are put to bed on their back on a firm, flat surface, in a crib, cradle or bassinet that meets today’s safety recommendations. The crib should be completely empty, aside from a fitted sheet.[1]

2What is the standard crib mattress size?

Standard North American crib mattresses usually measure 51 ⅝ to 53 inches in length and 27 ¼ to 28 inches in width.[5] Mini crib mattresses are considerably smaller at around 24 inches wide and 38 inches long.[6] There are exceptions since some crib and bassinet manufacturers sell proprietary mattresses to fit their products, but no matter what, it’s crucial to follow the Health Canada guidelines[1] about thickness and fit.

If you purchase a convertible crib, the mattress will still work when the crib is converted to a toddler bed. If you purchase a stand-alone toddler bed, you’ll need to measure the frame to ensure that you won’t need to purchase a second mattress.

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Safety Tip
Purchase fitted sheets designed for baby mattresses to ensure that the sheet fits tightly and won’t come loose, which is a potential hazard for your little one.[1] Twin mattress sheets are a lot larger and should not be used with a crib mattress.

3What are the different types of crib mattresses?

These are the three most common types of crib mattress:

Crib Mattress Type Features Pros Cons
Innerspring crib mattress Metal coils create firmness at the core of the mattress: the more coils, the firmer the mattress and more evenly distributed the support[7] Tends to have good edge support (meaning the edges don’t sag away from the crib frame as easily as some other models) More expensive and heavier than foam
Foam crib mattress Made from polyurethane
  • Lightweight (usually five to 13 pounds)
  • Tends to be less expensive than innerspring[8]
May have less edge support than an innerspring mattress
Dual-sided crib mattress Two-sided model has a firm side for infants and a slightly softer side for toddlers Lasts through to toddlerhood
  • Tends to be pricier
  • You’ll have to make sure you use the correct side
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Safety 1st Grow with Me 2-in-1 Crib Mattress

4What makes a baby mattress organic?

A crib mattress made with “organic” fibres isn’t necessarily better or safer for your baby.[10] However, if using natural materials and reducing chemical exposure (to pesticides, flame retardants or vinyl waterproofing) is important to you, check the manufacturer’s label for certain features:

  • Organic materials:  Organic baby mattresses are either innerspring or made from an approved organic material such as food-grade polyethylene. The mattress filling is also made from organic, natural fibres—think cotton or wool. Keep in mind that “natural” fibres may still be processed with pesticides, so you need to specifially look for organic fibres.[10]
  • No chemicals: Many certified organic mattress will avoid the use of chemical flame retardants and will stick to waterproofing that’s naturally derived.[11] However, some organic mattresses do use flame retardants. If you’re hoping to avoid these chemicals, make sure the crib mattress company discloses which flame retardants and waterproofing agents they use before you buy.
  • Certified status: A number of organic certifications may appear on the product, including the Global Organic Textile Standard (GOTS) and Greenguard Gold, which helps parents to know their mattress has a low emission rate and is made with non-toxic, sustainable materials.[12]

5How high should a crib’s mattress support be for a newborn?

To start, you may want to have the mattress support in the highest position to allow for less bending, which may be an issue for moms recovering from childbirth. But as soon as your baby can push themselves up onto their hands and knees, it’s time to move the mattress support to its lowest position.[1]

Sealy Naturalis 2-Stage Crib Mattress in a nursery

6What is a baby mattress cover and do I need one? What about a mattress pad?

  • Mattress covers and protectors: Most baby mattresses are waterproof, so there’s no need to purchase a mattress cover. If your mattress is only water-resistant, however, you can purchase a separate waterproof mattress cover.
  • Mattress pads: If you have a single-sided baby mattress that you intend to use through toddlerhood, you can buy a crib mattress pad that goes under the fitted sheet to add extra padding when your little one is big enough—meaning older than 12 months.[13] Some mattress pads are waterproof for added protection and they’re almost always machine-washable.

7How do I clean a crib mattress?

It’s a good idea to take a vacuum to your baby’s crib mattress whenever you change the sheets. This step will help to remove dust and other allergens. As for unexpected messes, it depends on the mattress and the stain. Before attempting to clean, check the label on your crib mattress for specific instructions, including what types of products you can use.

If you have a mattress cover, you can simply remove it and throw it in the washing machine.

If you don’t have a mattress cover, mattress cleanup usually takes three steps:

  1. Remove excess liquid: Gently soak it up with a clean sponge or paper towel. Don’t press too hard if your mattress isn’t waterproof.
  2. Add baby-safe soap and water: Use a clean sponge and don’t put soap directly on the stain. Gently wipe the area without pressing down too hard. Wring out and rinse your sponge until it’s clear of soap, then wipe the area. Repeat until there isn’t any soapy residue left on the mattress to irritate your baby’s skin.
  3. Dry thoroughly: Use a clean towel or allow to air dry. Then remake the crib with a fresh crib sheet.

If your baby mattress still has an odour after the stain has been treated and the mattress has fully dried, take it outside on a warm, sunny day, repeat the cleaning steps and let it dry completely in the sunshine. The UV rays will kill off the bacteria causing the offending odour.[14]

8How long is a baby mattress good for?

With regular wear and tear, a crib mattress should last about five years.[15] Even so, buying a second-hand crib mattress generally isn’t recommended because you can’t know how the crib mattress was cared for or stored. It could harbour bacteria or mould, have moisture trapped inside or be covered in harsh cleaning agents that aren’t safe for little ones.[16]

Cribs and Crib Mattresses

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This article is intended as general information. To be sure a product is right for you, always be sure to read and follow the label(s)/instruction(s) that accompany your product(s). Walmart will not be responsible for any injury or damage caused by this activity.