Choosing the best underwear for kids is a major milestone, whether you are just starting the potty training journey or you’ve been accident-free for months. It feels like a small detail, but the right pair can make a massive difference in your child’s comfort and confidence.
It is not just about grabbing the first multipack with a superhero on it. To avoid wedgies, itching, and refusal to get dressed, you need to think about a few specifics:
- Fabric: Breathability is non-negotiable.
- Fit: Snug vs. loose cuts.
- Durability: Surviving the wash cycle.
- Sensory Needs: Seams and tags matter.
We analyzed materials, tested durability, and checked for “wearability” to find the winners. Here are our top picks for the best underwear for kids to keep your little ones comfortable all day long.
- Soft fabric
- Cute and fun patterns
- Fast-drying fabric
- 100% organic
- Washes well
- Doesn’t shrink when washed
What Types of Kids Underwear Are Available?
Just like the adult aisle, the kids’ section is packed with various cuts and styles. Knowing the difference helps you pick the right fit for your child’s body type and preference.
Briefs
Briefs are the classic choice and work well for both boys and girls. They typically sit just below the belly button and offer a snug fit. The leg openings sit high at the hip crease, offering full freedom of movement for active legs.
Boxers
Modeled after adult shorts, boxers offer a loose, breezy fit. They usually feature a relaxed elastic waistband and loose leg openings. However, the excess fabric can sometimes bunch up under skinny jeans or leggings.
Boxer Briefs
This hybrid style gives you the best of both worlds. You get the longer leg coverage of a boxer with the snug, supportive fit of a brief. They are great for preventing chafing and stay in place well under pants.
Training Pants (Pull-Ups)
While some people use “pull-ups” to refer to disposable diapers, in the underwear world, these are thick, reusable cloth briefs. They look like big-kid undies but feature a hidden absorbent layer to catch small accidents while your child learns to get to the potty in time.
When Should Toddlers Wear Underwear?
The switch to underwear usually happens when you decide to start toilet training. There is no magic age, but most children show signs of readiness between 18 months and 3 years old (1).
Once you ditch the diapers, you have two main paths: go straight to regular thin underwear (the “cold turkey” method) or use thick training pants for a transition period. Your choice depends entirely on your tolerance for mess and your child’s personality.
Things to Consider
Material
Cotton is the gold standard for children’s underwear. It is breathable, absorbent, and soft against delicate skin. Many parents prefer organic cotton to ensure the fabric is free from pesticides and harsh chemicals. Synthetic blends can be durable, but they don’t breathe as well, which can lead to irritation or yeast infections in sensitive kids.
Durability
Kids are hard on clothes, and underwear is no exception. Between playground climbing and frequent washing (especially during potty training), you need fabric that holds up. Look for reinforced stitching and high-quality elastic that won’t unravel or lose its stretch after a few trips through the dryer.
Comfort
Comfort is usually the deciding factor for a child. Some hate the feeling of tight bands, while others need that snug security. Tagless labels are a lifesaver for preventing itchy necks and waistbands.
If your child has sensory processing issues, look for “seamless” varieties. These are knit in a single piece to eliminate the ridges that often irritate sensitive skin.
Appearance
You might not care if the underwear has a dinosaur or a plain stripe, but your child definitely does. Involving your child in the buying process can be a great motivator. Let them choose between two approved options. If they love the character on their bum, they are often more motivated to keep them dry.
Your Kid’s Age
For younger toddlers, ease of use is critical. Look for waistbands that are loose enough for little hands to pull up and down independently. Briefs with wider leg holes or “finger loops” can help them master the mechanics of toileting. Older kids usually prioritize style and concealment under their school clothes.
Product Reviews
We analyzed dozens of brands, checking for softness, shrink-resistance, and “wedgie potential.” These pairs came out on top.
Boboking Baby Soft Cotton Underwear
Best Girls Underwear
If you are looking for breathable staples that stay in place, these Boboking briefs are a fantastic choice for girls. We love that the cut sits slightly higher on the waist, which prevents that annoying “slip-down” effect active kids often deal with.
The construction focuses heavily on comfort. The fabric is 100% cotton, ensuring maximum breathability. Even better, the elastic waistband is fully encased in fabric, so no rubbery material ever touches your child’s skin. The double-layered crotch adds an extra measure of hygiene and durability.
Pros
- True to size: We found the sizing accurate, saving you the hassle of returns.
- Wash-friendly: The cotton holds up well to hot water and frequent laundering.
Cons
- Wide leg holes: The openings are generous, which might be too loose for very petite children.
Product Specs
| Style | Girls briefs |
| Material | 100% cotton |
| Sizes Available | 2T to 12 years |
| Number In Pack | Six |
| Colors/patterns available | 24 multipacks available from brights to pastels. |
Our Ratings
EZ Undeez Boys
Best Boys Underwear
These boxers were invented by parents specifically to help toddlers master the art of dressing themselves. The standout feature is the patented reinforced loops sewn into the waistband, allowing little fingers to hook in and pull up with ease.
Beyond the loops, the comfort level is high. The waistband is wide and soft to prevent digging, and the entire garment is tag-free. We also appreciate that the legs are loose enough to prevent constriction but long enough to count as proper boxer briefs.
Pros
- Styles for everyone: Also available in a briefs style if your child prefers less fabric.
- Leak protection: A lightly padded front zone catches small dribbles before they soak trousers.
- Longevity: The fabric resists pilling and fading over time.
Cons
- Runs small: The fit is snug; we recommend ordering one size up for comfort.
Product Specs
| Style | Boxers or briefs. |
| Material | Cotton |
| Sizes Available | 2T/3T and 4T/5T |
| Number In Pack | Four |
| Colors/patterns available | Six different theme packs are available. |
Our Ratings
Rocky Thermal Underwear/PJs
Best Thermal Kids Underwear
When the temperature drops, standard cotton briefs won’t cut it; this set from Rocky is the perfect base layer for winter days. The fleece-lined polyester fabric is exceptionally soft and traps body heat effectively to keep your child warm.
Despite being warm, the material is lightweight and stretchy. It hugs the body closely, allowing for full range of motion under snowsuits or school clothes. Because it is a two-piece set, it doubles perfectly as cozy winter pajamas.
Pros
- Warm when wet: Unlike cotton, the synthetic fibers retain some heat even if they get damp.
- Bulk-free: Thin enough to layer comfortably under jeans.
- Versatile: Works as underwear, loungewear, or sleepwear.
Cons
- Pricey: These cost significantly more per piece than standard underwear.
Product Specs
| Style | Long underwear with matching long-sleeved vest. |
| Material | 92% polyester, 8% spandex |
| Sizes Available | 2T to 7 |
| Number In Pack | One pair of long underwear and one long-sleeved vest per pack |
| Colors/patterns available | 23 colors and prints available. |
Our Ratings
VieGreenleaf Potty Training Skirt
Best Quick-Dry Kids Underwear
If you are battling nighttime leaks, this unique “skirt” offers a layer of insurance for your mattress. It isn’t traditional underwear; it is a waterproof skirt designed to be worn over regular undies or training pants during naps and bedtime.
The construction features three distinct layers: soft cotton on the outside, a waterproof TPU barrier in the middle, and absorbent bamboo on the inside. The high waist design helps keep the skirt in place even if your child tosses and turns.
Pros
- Soft feel: The bamboo inner layer is gentle and dries relatively quickly.
- Fun prints: The designs are kid-friendly without relying on licensed characters.
Cons
- Limited capacity: It helps with leaks but won’t contain a full bladder release from a heavy wetter.
Product Specs
| Style | Skirt |
| Material | Cotton, TPU waterproof, bamboo |
| Sizes Available | For babies 2 to 6 years of age |
| Number In Pack | Two pairs per pack |
| Colors/patterns available | Two different patterns per pack. |
Our Ratings
City Threads Boys Certified Organic Cotton Underwear
Best Kids Underwear For Sensitive Skin
For kids with eczema or easily irritated skin, City Threads offers a clean, chemical-free solution. These briefs are made in the USA using 100% certified organic cotton, meaning no pesticides or harsh dyes touch your child’s sensitive areas.
While some organic fabrics feel stiff, these are surprisingly soft right out of the package. They skip the fire retardants and insecticides often found in mass-market clothing. The waistband is fully encased in cotton, ensuring that latex elastic never rubs against the skin.
Pros
- Chemical-free: Peace of mind for parents worried about toxins and skin reactions.
- Durable: They resist shrinking and maintain their shape after months of washing.
Cons
- Tight legs: The leg openings run small, so consider sizing up if your child has thicker thighs.
Product Specs
| Style | Briefs |
| Material | 100% certified organic cotton |
| Sizes Available | 2T to 16 |
| Number In Pack | Three pairs per pack |
| Colors/patterns available | Six different packs available for boys and five for girls. |
Our Ratings
SmartKnitKids Seamless Undies
Best Seamless Underwear For Kids
If your child has sensory processing disorder (SPD) or just hates the feeling of clothes, SmartKnitKids is the answer. These are truly seamless garments, knitted much like a sock to eliminate bulky ridges at the sides and waist.
There is no elastic band to dig into the tummy, and absolutely no tags. The fabric is a high-stretch blend that hugs the body gently without feeling constrictive. They are designed to stay put, reducing the need for constant adjusting throughout the school day.
Pros
- Sensory friendly: Ideal for kids who are easily irritated by textures and seams.
- Gentle hug: The fabric provides light compression which can be soothing for some children.
- Domestic production: Designed and manufactured in the USA.
Cons
- Basic aesthetics: The color and style options are very limited compared to other brands.
Product Specs
| Style | Available in boxer briefs and “boy cut” briefs for girls |
| Material | 100% cotton |
| Sizes Available | 4 to 12 years |
| Number In Pack | Three |
| Colors/patterns available | One mixed pack for boxer briefs and one mixed pack for girls’ briefs. |
Our Ratings
Hudson Baby Kids Unisex Pants
Best Gender-Neutral Kids Underwear
Hudson Baby offers a practical middle ground between diapers and regular panties. These training pants are gender-neutral and feature a built-in absorbent pad that runs from the front waistband all the way to the back.
This design is excellent for the early days of potty training when accidents are frequent. They catch the bulk of the mess, saving your floors and car seats, but they still feel wet enough to alert your child that they missed a potty break.
Pros
- Easy care: The cotton/polyester blend handles machine washing and drying without fuss.
- Shape retention: They don’t bag out after washing, keeping a secure fit.
- Comfortable elastic: The leg and waist bands are firm enough to prevent leaks but soft enough to avoid red marks.
Cons
- Sizing varies: They tend to run small, so you may need to experiment to find the perfect fit.
Product Specs
| Style | Briefs with padding |
| Material | 100% cotton with polyester & PEVA padding |
| Sizes Available | 12 months to 4T |
| Number In Pack | Four per pack |
| Colors/patterns available | 3 different packs available with a total of 10 designs. |
Our Ratings
| Product | Best | Style | Material | Sizes Available |
| Boboking Baby Cotton Underwear | Girls | Girls briefs | 100% cotton | 2T-12 years |
| EZ Undeez Boys | Boys | Boxers, briefs. | Cotton | 2-3 years & 4-5 years |
| Rocky Thermal Underwear/PJs | Thermal | Long johns | 92% polyester, 8% spandex | 2T to 7 |
| VieGreenleaf Training Skirt | Quick-Dry | Skirt | TPU, cotton, bamboo | 2 to 6 years |
| City Threads Organic Cotton Underwear | Sensitive Skin | Briefs | 100% organic cotton | 2T to 16 years |
| SmartKnitKids Seamless Undies | Seamless | Boxer briefs | 100% cotton | 4 to 12 years |
| Hudson Baby Unisex Pants | Gender-Neutral | Briefs | 100% Cotton | 12 months to 4T |
FAQs
How Many Pairs of Underwear Do I Need for My Child?
We recommend having at least 10 to 14 pairs of underwear for your child. If you are in the middle of potty training, you might want to double that number (around 20 pairs) to account for multiple accidents per day without needing to run the washing machine constantly.
How Do I Know What Size Underwear to Buy?
Always prioritize weight and waist measurements over age when consulting sizing charts. Children grow at different rates, and size 4T in one brand might fit like a size 2T in another. If your child is between sizes, it is usually safer to size up for comfort and longevity.
Is 100% Cotton Better Than Synthetic Blends?
Generally, yes. 100% cotton is hypoallergenic and highly breathable, which prevents moisture buildup and yeast infections. However, synthetic blends (like polyester or spandex) are often stretchier and retain their shape better, which can be good for active sports or thermal layers.
