Warm baby socks are thick socks for cold days. They are knitted from fine merino wool, or have soft loops inside like a towel, and both hold a layer of warm air around the foot. Thin baby socks lie flat on the skin, for indoors and mild days.
Put them on outdoors below 12°C (54°F), inside baby booties, rain boots, winter boots, a pram suit or a stroller footmuff. Indoors, they are only for a cold floor during the day. One warm pair is all a foot needs.
- For ages0–3years
- You'll need3–4pairs per size
- Wear them below12°C54°F
One warm pair, not two
A second pair of socks feels like more warmth. Inside a snug boot, it does the opposite. A warm sock keeps the foot warm with the air held in its knit. Two pairs in a snug boot press that air out and squeeze the foot, so less warm blood reaches the toes. The toes end up colder than in one pair.
So put on one warm pair, in booties or boots with room for the toes to wiggle.
Two pairs:No room for warm air
- Not good: Tight in the boot
- Not good: Knit pressed flat
- Not good: Toes turn cold
One warm pair:Room for warm air
- Good: Room to wiggle the toes
- Good: Knit stays thick and soft
- Good: Toes stay warm
Types of warm baby socks
Merino wool socks
For cold walks, the stroller and boots below 12°C (54°F). A thick, soft knit of fine merino wool, with a little nylon and stretch (elastane) so the sock keeps its shape.
Terry-loop socks
For deeper cold below 8°C (46°F), and inside unlined rain boots. Soft loops, like a towel's, are knitted across the inside of the sole and leg, in merino wool or thick cotton. The loops hold the most warm air and pad the heel.
Grip-sole slipper socks
For cold wood or tile floors at home, once your baby pulls up to stand, cruises along furniture or walks. Silicone dots under the sole stop slipping, though a steady walker keeps slippers on better. Keep them out of outdoor shoes: the dots and the thick cuffs catch on the lining and crowd the toes.
Merino wool or thick cotton?
The two can look alike on the shelf, so read the label. What matters is what happens when feet sweat inside a closed boot.
Merino wool
The one for boots and long cold walks. Wool takes the sweat into the fiber, so the sock still feels dry on the skin.
- Good: Stays warm when damp
- Good: Warm without bulk in a boot
- Not good: Wool wash, then dried flat
Thick cotton terry
Fine for a cold floor at home or a covered stroller ride, where the feet stay dry.
- Good: Goes in the cotton wash
- Good: Fine on dry floors and rides
- Not good: Holds sweat inside a boot
How to choose and fit warm socks
1. Room for the sock in the boot
Try boots and booties on over the warm sock your baby will wear in them. Boots that only fit over a thin sock squeeze the foot once winter starts.
- Good: Room ahead of the toes
- Good: Opens wide over the sock
- Not good: Tight once the sock is on
2. Mostly merino, with a wide cuff
Look for mostly merino wool on the label, with some nylon (often printed as polyamide) for strength and 2–5% elastane, so the sock stays on the heel. A wide, fold-over ribbed cuff holds it up gently. For a strong kicker, pull the cuff up under the pants, or add baby booties with an ankle strap.
- Good: Mostly merino, some nylon
- Good: Cuff stays up through kicks
- Not good: Cuff leaves deep red marks
3. A smooth inside at the toes
Thick and patterned winter socks have more yarn inside: loops, and long strands behind the pattern. Turn the toe inside out before dressing: a stray hair or a long loose thread can wind tight around a toe (a hair tourniquet). Pick a flat, smooth toe seam that will not rub in a boot.
- Good: Toe seam lies flat
- Good: No loose threads inside
- Not good: Long threads across the toes
Questions parents ask
Can newborn babies wear wool socks, or are they itchy?
Yes, newborns can wear socks of fine merino wool, right on the skin. Coarse wool prickles because its thick fibers (above about 30 microns across) stay stiff. The superfine merino in baby socks is much thinner than a human hair (under 18.5 microns), so it bends softly against the skin.
Can a baby with eczema wear wool socks?
For skin with eczema, cotton is the usual first choice. Fine merino is much softer than ordinary wool, and it suits many babies with eczema too. Try one pair first, and go back to cotton if the skin turns red or itchy.
Should babies wear warm socks indoors and to sleep in winter?
Usually not. In a normally heated room (16–20°C, 61–68°F), a footed sleepsuit, a sleep bag or a pair of thin baby socks is enough. Skip thick wool or fleece socks inside a footed sleepsuit or a winter sleep bag at night, because the extra layer traps heat. A baby's hands and feet are normally cooler than the body, so feel the chest or the back of the neck instead.
Why were my toddler's feet cold and damp inside winter boots?
Usually cotton socks, a tight boot, or both. Feet sweat in insulated winter boots and rubber rain boots, and cotton holds that sweat on the skin, so the toes cool as soon as your child stops moving. Put on one pair of terry-loop merino socks, in a boot with about a thumb's width of room ahead of the toes. Change out of damp socks right after you come in.
Are 100% wool socks better than a wool blend?
For a baby who does not walk yet, resting in a stroller or a carrier, a loose sock of pure wool works like a little sweater for the foot. Once your baby crawls, pulls to stand or walks in shoes, pure wool stretches out at the ankle and wears through at the heel fast. A blend of mostly merino with a little nylon and elastane keeps the warmth of wool, stays on the heel and lasts through many washes.
Why are some merino wool baby socks so thin, and can babies wear them in mild weather?
Merino names the fiber, not how thick the sock is. A flat-knit merino sock with no loops inside is as thin as a cotton dress sock, and it breathes well in closed shoes in spring and autumn. For deeper cold below 8°C (46°F), look for socks sold as terry-loop, cushioned or plush inside: the loops hold the warm air.
How do I wash wool baby socks so they do not shrink?
Turn merino socks inside out, so the outside does not pill. Wash them at 30°C (86°F) on a wool or delicate cycle with a mild wool detergent without enzymes, or soak them for 10 minutes in lukewarm water. Skip the hot dryer and lay them flat, away from radiators. Many everyday merino baby socks are treated so they will not shrink in a gentle machine wash: the care tag often says superwash wool.
