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Whether it's a day at the pool or the beach, your little man needs a comfortable and stylish look. At thredUP, you'll find boys' swimwear in a variety of styles, colors, and designs that he will love, and at up to 90% off estimated retail, the prices will make you happy as well.

5TRemove filter12-18 moRemove filter
78 items
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    Just One Rash Guard (view 2)Just One Rash Guard (view 1)
    View Product: Just One Rash Guard

    Just One

    Rash Guard
    Size 5T
    $10.99
    45% off estimated retail
    SwimZip Rash Guard (view 2)SwimZip Rash Guard (view 1)
    View Product: SwimZip Rash Guard

    SwimZip

    Rash Guard
    Size 5T
    $11.99
    55% off estimated retail
    Old Navy Rash Guard (view 2)Old Navy Rash Guard (view 1)
    View Product: Old Navy Rash Guard

    Old Navy

    Rash Guard
    Size 12-18 mo
    $9.99
    28% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99
    43% off estimated retail
    The Edit. Forever Classic, Get perfectly polished in trousers, blazers, and more. Shop The Edit
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99
    43% off estimated retail
    Janie and Jack Board Shorts (view 2)Janie and Jack Board Shorts (view 1)
    View Product: Janie and Jack Board Shorts

    Janie and Jack

    Board Shorts
    Size 12-18 mo
    $7.99
    55% off estimated retail
    UV Skinz Rash Guard (view 2)UV Skinz Rash Guard (view 1)
    View Product: UV Skinz Rash Guard

    UV Skinz

    Rash Guard
    Size 12-18 mo
    $13.99
    48% off estimated retail
    Rugged Butts Rash Guard (view 2)Rugged Butts Rash Guard (view 1)
    View Product: Rugged Butts Rash Guard

    Rugged Butts

    Rash Guard
    Size 12-18 mo
    $8.99
    43% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Unbranded Wetsuit (view 2)Unbranded Wetsuit (view 1)
    View Product: Unbranded Wetsuit

    Unbranded

    Wetsuit
    Size 12-18 mo
    $14.99 $11.99 20% off with code SHINE
    65% off estimated retail
    Marvel Rash Guard (view 2)Marvel Rash Guard (view 1)
    View Product: Marvel Rash Guard

    Marvel

    Rash Guard
    Size 5T
    $21.99 $15.39 30% off with code SHINE
    50% off estimated retail
    Old Navy Rash Guard (view 2)Old Navy Rash Guard (view 1)
    View Product: Old Navy Rash Guard

    Old Navy

    Rash Guard
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    35% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    66% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $10.99 $8.79 20% off with code SHINE
    31% off estimated retail
    Janie and Jack Board Shorts (view 2)Janie and Jack Board Shorts (view 1)
    View Product: Janie and Jack Board Shorts

    Janie and Jack

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    50% off estimated retail
    Janie and Jack Board Shorts (view 2)Janie and Jack Board Shorts (view 1)
    View Product: Janie and Jack Board Shorts

    Janie and Jack

    Board Shorts
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    44% off estimated retail
    Rugged Butts Rash Guard (view 2)Rugged Butts Rash Guard (view 1)
    View Product: Rugged Butts Rash Guard

    Rugged Butts

    Rash Guard
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    50% off estimated retail
    Sunuva Rash Guard (view 2)Sunuva Rash Guard (view 1)
    View Product: Sunuva Rash Guard

    Sunuva

    Rash Guard
    Size 12-18 mo
    $16.99 $13.59 20% off with code SHINE
    61% off estimated retail
    LC Waikiki Board Shorts (view 2)LC Waikiki Board Shorts (view 1)
    View Product: LC Waikiki Board Shorts

    LC Waikiki

    Board Shorts
    Size 12-18 mo
    $11.99 $9.59 20% off with code SHINE
    $11
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $11.99 $9.59 20% off with code SHINE
    42% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    52% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    61% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $11.99 $9.59 20% off with code SHINE
    42% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Carter's Board Shorts (view 2)Carter's Board Shorts (view 1)
    View Product: Carter's Board Shorts

    Carter's

    Board Shorts
    Size 12-18 mo
    $12.99 $10.39 20% off with code SHINE
    56% off estimated retail
    Tea Board Shorts (view 2)Tea Board Shorts (view 1)
    View Product: Tea Board Shorts

    Tea

    Board Shorts
    Size 12-18 mo
    $14.99 $10.49 30% off with code SHINE
    59% off estimated retail
    UV Skinz Rash Guard (view 2)UV Skinz Rash Guard (view 1)Price Drop
    View Product: UV Skinz Rash Guard

    UV Skinz

    Rash Guard
    Size 12-18 mo
    $12.99 $7.79 40% off with code SHINE
    51% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)Price Drop
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    56% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 12-18 mo
    $4.99 $3.99 20% off with code SHINE
    81% off estimated retail
    UV Skinz Board Shorts (view 2)UV Skinz Board Shorts (view 1)
    View Product: UV Skinz Board Shorts

    UV Skinz

    Board Shorts
    Size 12-18 mo
    $10.99 $8.79 20% off with code SHINE
    38% off estimated retail
    Tommy Hilfiger Board Shorts (view 2)Tommy Hilfiger Board Shorts (view 1)
    View Product: Tommy Hilfiger Board Shorts

    Tommy Hilfiger

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    50% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    50% off estimated retail
    UV Skinz Board Shorts (view 2)UV Skinz Board Shorts (view 1)Price Drop
    View Product: UV Skinz Board Shorts

    UV Skinz

    Board Shorts
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    44% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)Price Drop
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    66% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)Price Drop
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)Price Drop
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    66% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)Price Drop
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    66% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)Price Drop
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    The Children's Place Board Shorts (view 2)The Children's Place Board Shorts (view 1)Price Drop
    View Product: The Children's Place Board Shorts

    The Children's Place

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Old Navy Rash Guard (view 2)Old Navy Rash Guard (view 1)Price Drop
    View Product: Old Navy Rash Guard

    Old Navy

    Rash Guard
    Size 12-18 mo
    $6.99 $5.59 20% off with code SHINE
    50% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    37% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)Price Drop
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    52% off estimated retail
    Baby Gap Rash Guard (view 2)Baby Gap Rash Guard (view 1)Price Drop
    View Product: Baby Gap Rash Guard

    Baby Gap

    Rash Guard
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    37% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)Price Drop
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)Price Drop
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    63% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $9.99 $7.99 20% off with code SHINE
    37% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)Price Drop
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Old Navy Rash Guard (view 2)Old Navy Rash Guard (view 1)Price Drop
    View Product: Old Navy Rash Guard

    Old Navy

    Rash Guard
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    35% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    42% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    43% off estimated retail
    Old Navy Rash Guard (view 2)Old Navy Rash Guard (view 1)Price Drop
    View Product: Old Navy Rash Guard

    Old Navy

    Rash Guard
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    35% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    40% off estimated retail
    UV Skinz Rash Guard (view 2)UV Skinz Rash Guard (view 1)Price Drop
    View Product: UV Skinz Rash Guard

    UV Skinz

    Rash Guard
    Size 12-18 mo
    $8.99 $6.29 30% off with code SHINE
    65% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)Price Drop
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    63% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)Price Drop
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    64% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    40% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    40% off estimated retail
    Assorted Brands Rash Guard (view 2)Assorted Brands Rash Guard (view 1)Price Drop
    View Product: Assorted Brands Rash Guard

    Assorted Brands

    Rash Guard
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    60% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    40% off estimated retail
    Baby Gap Board Shorts (view 2)Baby Gap Board Shorts (view 1)Price Drop
    View Product: Baby Gap Board Shorts

    Baby Gap

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    55% off estimated retail
    OshKosh B'gosh Rash Guard (view 2)OshKosh B'gosh Rash Guard (view 1)
    View Product: OshKosh B'gosh Rash Guard

    OshKosh B'gosh

    Rash Guard
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    57% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    40% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $8.99 $7.19 20% off with code SHINE
    40% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    46% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)Price Drop
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    46% off estimated retail
    Old Navy Rash Guard (view 2)Old Navy Rash Guard (view 1)Price Drop
    View Product: Old Navy Rash Guard

    Old Navy

    Rash Guard
    Size 12-18 mo
    $6.99 $5.59 20% off with code SHINE
    46% off estimated retail
    Unbranded Rash Guard (view 2)Unbranded Rash Guard (view 1)Price Drop
    View Product: Unbranded Rash Guard

    Unbranded

    Rash Guard
    Size 12-18 mo
    $7.99 $6.39 20% off with code SHINE
    60% off estimated retail
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