5 Little Monkeys Kids Mattress
A purpose-built sleep system for children aged 3 to 18, with organic cotton covers, CertiPUR-US certified foam, and a waterproof protector included in every bundle.
4.9/5 ★
1,648 reviews
Ages 3-18
Designed for
$399
Starting price
100-night
Risk-free trial
Quick Answer
The 5 Little Monkeys is one of the highest-rated kids mattresses on the market, with a 4.9/5 average across 1,600+ parent reviews. It ships as a complete sleep system (mattress, protector, pillow, and sheets in the bundle version) and comes in Twin, Full, and Queen. The Original Memory Foam starts at $399 for a Twin. Every order includes a stuffed monkey plushie.
5 Little Monkeys Original Memory Foam Mattress
What Makes This a Kids Mattress?
Most mattresses are engineered for adult body weight, typically 150 to 200+ pounds spread across a larger frame. Children weigh far less and generate more body heat relative to their size. The 5 Little Monkeys addresses both of these realities. Its 8-inch foam construction uses a softer density that responds to lighter bodies, where a standard medium-firm adult mattress would feel like sleeping on plywood to a 50-pound seven-year-old. A phase-change temperature regulation layer actively absorbs and releases heat, keeping the sleeping surface cooler than traditional memory foam. The organic cotton cover is removable and machine-washable, which matters far more when the sleeper is a kid who occasionally spills juice at bedtime.
Construction and Materials
The Original Memory Foam model is an 8-inch mattress built in three layers: a 1.5-inch gel memory foam comfort layer on top, a transitional memory foam layer in the middle, and a 5-inch polyurethane foam support base. The Advanced Hybrid model adds an inch of height (9 inches total) by incorporating a pocketed coil support system beneath the foam layers, which improves airflow and provides more responsive bounce. Both models use an organic cotton cover with OEKO-TEX certification. The foam is CertiPUR-US certified and GREENGUARD Gold certified, meaning it has been independently tested for low chemical emissions. Both are completely fiberglass-free.
The Sleep System Bundle
While the mattress is available standalone, the bundle version is the flagship product. It includes the mattress, a waterproof mattress protector (organic cotton, hypoallergenic), a fitted sheet set, and a custom-fill pillow. Every order also ships with a stuffed monkey plushie, which kids tend to love. The bundle pricing runs roughly 35-40% higher than the mattress alone, but buying the protector, sheets, and pillow separately would cost more. For a first kids bed setup, the bundle is the more practical choice.
Firmness and Comfort
The Original Memory Foam sits at roughly a 7 out of 10 on the firmness scale, which the brand calls Cushion Firm. That is firmer than most adult memory foam mattresses, and deliberately so. Children's spines are still developing, and a firmer sleeping surface helps maintain proper alignment as they grow. The mattress still has enough give to relieve pressure points at the shoulders and hips for side sleepers. The Hybrid model feels slightly firmer and more responsive thanks to its coil system, with less of the slow-sinking feel that pure memory foam produces.
Sizing for Kids' Rooms
The 5 Little Monkeys comes in three standard sizes: Twin (38x75 inches), Full (54x75 inches), and Queen (60x80 inches). For most kids' bedrooms between 8x10 and 10x10 feet, a Twin is the practical choice. It leaves room for a desk, bookshelf, and play area. A Full works well in shared rooms or when a child wants more rolling space, but the room should be at least 10x10 feet. The Queen is better suited for teenagers or kids who will grow into the mattress over many years. At 60x80 inches, it needs a room 10x10 feet or larger with furniture.
5 Little Monkeys Pricing by Size
Prices are approximate and may vary. All links go to the product on Amazon.
Original Memory Foam (8 inch)
Advanced Hybrid (9 inch)
Memory Foam Bundle (Mattress + Protector + Sheets + Pillow)
Pros and Cons
Strengths
- +Designed specifically for kids' lighter body weight
- +Organic cotton cover, removable and washable
- +CertiPUR-US + GREENGUARD Gold + OEKO-TEX certified
- +Phase-change temperature regulation layer
- +Completely fiberglass-free
Weaknesses
- -Only three sizes (Twin, Full, Queen)
- -Higher price than generic kids mattresses
- -100-night trial is shorter than some adult brands
Frequently Asked Questions
What age range is the 5 Little Monkeys mattress for?
The brand designs for children aged 3 through 18. The foam density and firmness are calibrated for lighter body weights (roughly 30 to 150 pounds), but the Queen size works for average-weight teens and young adults as well.
Is the 5 Little Monkeys mattress safe for kids?
It carries three independent certifications: CertiPUR-US (foam tested for harmful chemicals), GREENGUARD Gold (low chemical emissions, safe for children and schools), and OEKO-TEX (textiles tested for harmful substances). It is also completely fiberglass-free.
What size 5 Little Monkeys mattress should I get?
Twin (38x75 inches) fits most kids' rooms and works for children up to about 5 foot 10. Full (54x75 inches) is better for shared rooms or kids who spread out. Queen (60x80 inches) suits teenagers who will use the mattress for years. Use our room size calculator to check which size fits your child's bedroom with furniture.
Does it come with a mattress protector?
The bundle version includes a waterproof mattress protector, fitted sheets, and a pillow. The standalone mattress does not include these accessories, but the protector is available separately on Amazon.
How firm is the 5 Little Monkeys mattress?
The Original Memory Foam is a 7 out of 10 (Cushion Firm), firmer than most adult memory foam mattresses. This is intentional: firmer support helps children's developing spines maintain proper alignment. The Hybrid model is slightly firmer at roughly 7.5 out of 10.
Can adults sleep on the 5 Little Monkeys mattress?
Light to average-weight adults (under 180 pounds) can sleep comfortably on the Queen size. Heavier adults will likely bottom out through the 8-inch foam stack and need a thicker, denser mattress designed for adult weight distribution.
What is the return policy?
The 5 Little Monkeys mattress comes with a 100-night trial. If the mattress is not the right fit, you can return it within that window for a full refund. The warranty covers 15 years.
Does it work with bunk beds?
The 8-inch Original Memory Foam meets most bunk bed height requirements (typically 8 inches or under). Check your bunk bed manufacturer's maximum mattress thickness before ordering. The 9-inch Hybrid may be too thick for some bunk bed safety rails.
Which Size Fits Your Child's Room?
Wondering which size fits your child's room? Our calculator factors in room dimensions, furniture, doors, and closets to find the largest mattress that fits with comfortable walking clearance.
Try the Mattress Size Calculator