Boys' Activewear

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Cater to your boys' busy lifestyles with affordable activewear from thredUP. Enjoy steep savings with prices up to 90% off estimated retail when you shop our extensive collection of hoodies, tops, shorts, and pants.

20,101 items
Under Armour Size 16

View Product: Under Armour Size 16

Under Armour

Size 16
$21.99 $38
Nike Size 7

View Product: Nike Size 7

Nike

Size 7
$8.99 $25

$6.29 30% off with

Weekend A'la Mer Size 18 mo

View Product: Weekend A'la Mer Size 18 mo

Weekend A'la Mer

Size 18 mo
$8.99 $34

$6.29 30% off with

Janie and Jack Size 6-12 mo

View Product: Janie and Jack Size 6-12 mo

Janie and Jack

Size 6-12 mo
$8.99 $34

$6.29 30% off with

Weekend A'la Mer Size 24 mo

View Product: Weekend A'la Mer Size 24 mo

Weekend A'la Mer

Size 24 mo
$8.99 $34

$6.29 30% off with

Fila Size 8

View Product: Fila Size 8

Fila

Size 8
$11.99 $26

$8.39 30% off with

Lands' End Size 18

View Product: Lands' End Size 18

Lands' End

Size 18
$8.99 $31

$6.29 30% off with

Adidas Size 3T

View Product: Adidas Size 3T

Adidas

Size 3T
$8.99 $32

$6.29 30% off with

Puma Size 4T

View Product: Puma Size 4T

Puma

Size 4T
$8.99 $26

$6.29 30% off with

Sport-Tek Size X-Small  kids

View Product: Sport-Tek Size X-Small kids

Sport-Tek

Size X-Small kids
$10.99 $26

$7.69 30% off with

Carter's Size 12 mo

View Product: Carter's Size 12 mo

Carter's

Size 12 mo
$7.99 $27

$5.59 30% off with

Janie and Jack Size 6-12 mo

View Product: Janie and Jack Size 6-12 mo

Janie and Jack

Size 6-12 mo
$10.99 $34

$7.69 30% off with

Adidas Size 5

View Product: Adidas Size 5

Adidas

Size 5
$7.99 $32

$5.59 30% off with

Gymboree Size Newborn

View Product: Gymboree Size Newborn

Gymboree

Size Newborn
$7.99 $18

$5.59 30% off with

Colosseum Athletics Size 3-6 mo

View Product: Colosseum Athletics Size 3-6 mo

Colosseum Athletics

Size 3-6 mo
$10.99 $27

$7.69 30% off with

Old Navy Size 18-24 mo

View Product: Old Navy Size 18-24 mo

Old Navy

Size 18-24 mo
$7.99 $20

$5.59 30% off with

Gymboree Size 6-12 mo

View Product: Gymboree Size 6-12 mo

Gymboree

Size 6-12 mo
$10.99 $18

$7.69 30% off with

Gymboree Size 5T

View Product: Gymboree Size 5T

Gymboree

Size 5T
$7.99 $35

$5.59 30% off with

Active by Old Navy Size 14

View Product: Active by Old Navy Size 14

Active by Old Navy

Size 14
$7.99 $19

$5.59 30% off with

Reebok Size 10

View Product: Reebok Size 10

Reebok

Size 10
$7.99 $38

$5.59 30% off with

Lands' End Size 12

View Product: Lands' End Size 12

Lands' End

Size 12
$7.99 $31

$5.59 30% off with

Lands' End Size 14

View Product: Lands' End Size 14

Lands' End

Size 14
$7.99 $31

$5.59 30% off with

Under Armour Size 3-6 mo
Price Drop BadgePrice Drop

View Product: Under Armour Size 3-6 mo

Under Armour

Size 3-6 mo
$16.99 $38

$8.49 50% off with

Under Armour Size X-Large youth

View Product: Under Armour Size X-Large youth

Under Armour

Size X-Large youth
$12.99 $38

$9.09 30% off with

Nike Golf Size Medium youth

View Product: Nike Golf Size Medium youth

Nike Golf

Size Medium youth
$12.99 $31

$9.09 30% off with

Under Armour Size Large youth

View Product: Under Armour Size Large youth

Under Armour

Size Large youth
$15.99 $26

$11.19 30% off with

Under Armour Size Small youth
Price Drop BadgePrice Drop

View Product: Under Armour Size Small youth

Under Armour

Size Small youth
$12.99 $26

$6.49 50% off with

Under Armour Size Small youth
Price Drop BadgePrice Drop

View Product: Under Armour Size Small youth

Under Armour

Size Small youth
$13.99 $26

$8.39 40% off with

Under Armour Size 6

View Product: Under Armour Size 6

Under Armour

Size 6
$12.99 $26

$9.09 30% off with

Under Armour Size 7

View Product: Under Armour Size 7

Under Armour

Size 7
$12.99 $38

$9.09 30% off with

Kids By Exist Size X-Large kids

View Product: Kids By Exist Size X-Large kids

Kids By Exist

Size X-Large kids
$11.99 $20

$7.19 40% off with

Nike Size Medium youth

View Product: Nike Size Medium youth

Nike

Size Medium youth
$10.99 $38

$7.69 30% off with

Nike Size Small youth

View Product: Nike Size Small youth

Nike

Size Small youth
$13.99 $38

$9.79 30% off with

Adidas Size Large kids

View Product: Adidas Size Large kids

Adidas

Size Large kids
$10.99 $26

$7.69 30% off with

Adidas Size 7

View Product: Adidas Size 7

Adidas

Size 7
$9.99 $38

$6.99 30% off with

Nike Size Medium kids

View Product: Nike Size Medium kids

Nike

Size Medium kids
$12.99 $25

$9.09 30% off with

H&M Size Preemie

View Product: H&M Size Preemie

H&M

Size Preemie
$9.99 $15

$6.99 30% off with

Puma Size 14

View Product: Puma Size 14

Puma

Size 14
$9.99 $31

$6.99 30% off with

Baby Gap Size 12-18 mo

View Product: Baby Gap Size 12-18 mo

Baby Gap

Size 12-18 mo
$8.99 $30

$6.29 30% off with

Nike Size Small youth

View Product: Nike Size Small youth

Nike

Size Small youth
$11.99 $25

$8.39 30% off with

Adidas Size 6

View Product: Adidas Size 6

Adidas

Size 6
$11.99 $26

$8.39 30% off with

Nike Size Small youth

View Product: Nike Size Small youth

Nike

Size Small youth
$8.99 $25

$6.29 30% off with

Nike Size 6

View Product: Nike Size 6

Nike

Size 6
$11.99 $25

$8.39 30% off with

Active by Old Navy Size 8

View Product: Active by Old Navy Size 8

Active by Old Navy

Size 8
$8.99 $19

$6.29 30% off with

Adidas Size 8

View Product: Adidas Size 8

Adidas

Size 8
$8.99 $26

$6.29 30% off with

Nautica Size 4T

View Product: Nautica Size 4T

Nautica

Size 4T
$8.99 $34

$6.29 30% off with

STX Size 10

View Product: STX Size 10

STX

Size 10
$8.99 $31

$6.29 30% off with

Active by Old Navy Size 8

View Product: Active by Old Navy Size 8

Active by Old Navy

Size 8
$8.99 $19

$6.29 30% off with

Carter's Size 6 mo
Price Drop BadgePrice Drop

View Product: Carter's Size 6 mo

Carter's

Size 6 mo
$11.99 $20

$7.19 40% off with

Gap Kids Size Small kids

View Product: Gap Kids Size Small kids

Gap Kids

Size Small kids
$15.99 $40

$12.79 20% off with