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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.

8Remove filter3-6 moRemove filter
84 items
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    Thereabouts Rash Guard (view 2)Thereabouts Rash Guard (view 1)
    View Product: Thereabouts Rash Guard

    Thereabouts

    Rash Guard
    Size 8
    $11.99
    63% off estimated retail
    Lands' End Board Shorts (view 2)Lands' End Board Shorts (view 1)
    View Product: Lands' End Board Shorts

    Lands' End

    Board Shorts
    Size 8
    $11.99
    45% off estimated retail
    Hanna Andersson Board Shorts (view 2)Hanna Andersson Board Shorts (view 1)
    View Product: Hanna Andersson Board Shorts

    Hanna Andersson

    Board Shorts
    Size 8
    $17.99
    40% off estimated retail
    OshKosh B'gosh Board Shorts (view 2)OshKosh B'gosh Board Shorts (view 1)
    View Product: OshKosh B'gosh Board Shorts

    OshKosh B'gosh

    Board Shorts
    Size 8
    $8.99
    57% off estimated retail
    The Edit. Forever Classic, Get perfectly polished in trousers, blazers, and more. Shop The Edit
    Nautica Board Shorts (view 2)Nautica Board Shorts (view 1)
    View Product: Nautica Board Shorts

    Nautica

    Board Shorts
    Size 8
    $13.99
    36% off estimated retail
    Old Navy Board Shorts (view 2)Old Navy Board Shorts (view 1)New With Tags
    View Product: Old Navy Board Shorts

    Old Navy

    Board Shorts
    Size 8
    $11.99
    55% 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 8
    $11.99
    53% off estimated retail
    Lands' End Board Shorts (view 2)Lands' End Board Shorts (view 1)
    View Product: Lands' End Board Shorts

    Lands' End

    Board Shorts
    Size 8
    $9.99
    54% off estimated retail
    Nukutavake Board Shorts (view 2)Nukutavake Board Shorts (view 1)
    View Product: Nukutavake Board Shorts

    Nukutavake

    Board Shorts
    Size 8
    $20.99
    48% off estimated retail
    Gap Kids Board Shorts (view 2)Gap Kids Board Shorts (view 1)
    View Product: Gap Kids Board Shorts

    Gap Kids

    Board Shorts
    Size 8
    $15.99
    50% off estimated retail
    Orlebar Brown Board Shorts (view 2)Orlebar Brown Board Shorts (view 1)Flawed Gem
    View Product: Orlebar Brown Board Shorts

    Orlebar Brown

    Board Shorts
    Size 8
    $25.99
    91% off estimated retail
    Columbia Board Shorts (view 2)Columbia Board Shorts (view 1)
    View Product: Columbia Board Shorts

    Columbia

    Board Shorts
    Size 8
    $13.99
    36% off estimated retail
    Kanu Surf Board Shorts (view 2)Kanu Surf Board Shorts (view 1)
    View Product: Kanu Surf Board Shorts

    Kanu Surf

    Board Shorts
    Size 8
    $12.99 $10.39 20% off with code HOTDEAL
    40% off estimated retail
    Lands' End Board Shorts (view 2)Lands' End Board Shorts (view 1)
    View Product: Lands' End Board Shorts

    Lands' End

    Board Shorts
    Size 8
    $10.99 $8.79 20% off with code HOTDEAL
    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 3-6 mo
    $10.99 $8.79 20% off with code HOTDEAL
    38% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $14.99 $11.24 25% off with code HOTDEAL
    34% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $14.99 $11.24 25% off with code HOTDEAL
    34% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $13.99 $10.49 25% off with code HOTDEAL
    39% 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 3-6 mo
    $5.99 $4.79 20% off with code HOTDEAL
    57% off estimated retail
    Koala Kids Rash Guard (view 2)Koala Kids Rash Guard (view 1)New With Tags
    View Product: Koala Kids Rash Guard

    Koala Kids

    Rash Guard
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    27% off estimated retail
    Assorted Brands Board Shorts (view 2)Assorted Brands Board Shorts (view 1)
    View Product: Assorted Brands Board Shorts

    Assorted Brands

    Board Shorts
    Size 3-6 mo
    $5.99 $4.79 20% off with code HOTDEAL
    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 3-6 mo
    $5.99 $4.79 20% off with code HOTDEAL
    57% off estimated retail
    Koala Kids Rash Guard (view 2)Koala Kids Rash Guard (view 1)New With Tags
    View Product: Koala Kids Rash Guard

    Koala Kids

    Rash Guard
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    27% off estimated retail
    Koala Kids Rash Guard (view 2)Koala Kids Rash Guard (view 1)New With Tags
    View Product: Koala Kids Rash Guard

    Koala Kids

    Rash Guard
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    27% off estimated retail
    Under Armour Wetsuit (view 2)Under Armour Wetsuit (view 1)
    View Product: Under Armour Wetsuit

    Under Armour

    Wetsuit
    Size 3-6 mo
    $24.99 $18.74 25% off with code HOTDEAL
    54% off estimated retail
    OAS Board Shorts (view 2)OAS Board Shorts (view 1)
    View Product: OAS Board Shorts

    OAS

    Board Shorts
    Size 8
    $25.99 $20.79 20% off with code HOTDEAL
    65% off estimated retail
    Assorted Brands Rash Guard (view 2)Assorted Brands Rash Guard (view 1)
    View Product: Assorted Brands Rash Guard

    Assorted Brands

    Rash Guard
    Size 3-6 mo
    $10.99 $8.24 25% off with code HOTDEAL
    50% 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 3-6 mo
    $10.99 $8.79 20% off with code HOTDEAL
    21% off estimated retail
    PELAGIC Board Shorts (view 2)PELAGIC Board Shorts (view 1)New With Tags
    View Product: PELAGIC Board Shorts

    PELAGIC

    Board Shorts
    Size 8
    $17.99 $11.69 35% off with code HOTDEAL
    59% 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 3-6 mo
    $11.99 $9.59 20% off with code HOTDEAL
    42% off estimated retail
    I Play Board Shorts (view 2)I Play Board Shorts (view 1)
    View Product: I Play Board Shorts

    I Play

    Board Shorts
    Size 3-6 mo
    $5.99 $4.79 20% off with code HOTDEAL
    14% off estimated retail
    Cat & Jack Board Shorts (view 2)Cat & Jack Board Shorts (view 1)
    View Product: Cat & Jack Board Shorts

    Cat & Jack

    Board Shorts
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    38% off estimated retail
    Wonder Nation Rash Guard (view 2)Wonder Nation Rash Guard (view 1)New With Tags
    View Product: Wonder Nation Rash Guard

    Wonder Nation

    Rash Guard
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    18% off estimated retail
    Wonder Nation Rash Guard (view 2)Wonder Nation Rash Guard (view 1)New With Tags
    View Product: Wonder Nation Rash Guard

    Wonder Nation

    Rash Guard
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    18% off estimated retail
    Carter's Rash Guard (view 2)Carter's Rash Guard (view 1)Price Drop
    View Product: Carter's Rash Guard

    Carter's

    Rash Guard
    Size 3-6 mo
    $12.99 $9.74 25% off with code HOTDEAL
    50% 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 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    57% off estimated retail
    Hanna Andersson Board Shorts (view 2)Hanna Andersson Board Shorts (view 1)
    View Product: Hanna Andersson Board Shorts

    Hanna Andersson

    Board Shorts
    Size 3-6 mo
    $19.99 $10.99 45% off with code HOTDEAL
    33% off estimated retail
    Nickelodeon Board Shorts (view 2)Nickelodeon Board Shorts (view 1)
    View Product: Nickelodeon Board Shorts

    Nickelodeon

    Board Shorts
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    18% off estimated retail
    Cat & Jack Board Shorts (view 2)Cat & Jack Board Shorts (view 1)Price Drop
    View Product: Cat & Jack Board Shorts

    Cat & Jack

    Board Shorts
    Size 3-6 mo
    $6.99 $5.59 20% off with code HOTDEAL
    46% 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 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    55% off estimated retail
    Cat & Jack Rash Guard (view 2)Cat & Jack Rash Guard (view 1)
    View Product: Cat & Jack Rash Guard

    Cat & Jack

    Rash Guard
    Size 3-6 mo
    $11.99 $9.59 20% off with code HOTDEAL
    20% 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 3-6 mo
    $6.99 $5.59 20% off with code HOTDEAL
    50% off estimated retail
    Nickelodeon Board Shorts (view 2)Nickelodeon Board Shorts (view 1)
    View Product: Nickelodeon Board Shorts

    Nickelodeon

    Board Shorts
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    18% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $11.99 $9.59 20% off with code HOTDEAL
    47% off estimated retail
    Cat & Jack Rash Guard (view 2)Cat & Jack Rash Guard (view 1)
    View Product: Cat & Jack Rash Guard

    Cat & Jack

    Rash Guard
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    46% off estimated retail
    Cat & Jack Rash Guard (view 2)Cat & Jack Rash Guard (view 1)
    View Product: Cat & Jack Rash Guard

    Cat & Jack

    Rash Guard
    Size 3-6 mo
    $11.99 $9.59 20% off with code HOTDEAL
    20% off estimated retail
    H&M Board Shorts (view 2)H&M Board Shorts (view 1)Price Drop
    View Product: H&M Board Shorts

    H&M

    Board Shorts
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    42% 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 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    35% 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 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    28% off estimated retail
    Target Rash Guard (view 2)Target Rash Guard (view 1)Price Drop
    View Product: Target Rash Guard

    Target

    Rash Guard
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    27% off estimated retail
    Cat & Jack Board Shorts (view 2)Cat & Jack Board Shorts (view 1)
    View Product: Cat & Jack Board Shorts

    Cat & Jack

    Board Shorts
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    30% off estimated retail
    Soft Gallery Board Shorts (view 2)Soft Gallery Board Shorts (view 1)Price Drop
    View Product: Soft Gallery Board Shorts

    Soft Gallery

    Board Shorts
    Size 3-6 mo
    $17.99 $12.59 30% off with code HOTDEAL
    50% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)Price Drop
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 3-6 mo
    $10.99 $8.79 20% off with code HOTDEAL
    59% off estimated retail
    Janie and Jack Rash Guard (view 2)Janie and Jack Rash Guard (view 1)Price Drop
    View Product: Janie and Jack Rash Guard

    Janie and Jack

    Rash Guard
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    71% off estimated retail
    Nickelodeon Board Shorts (view 2)Nickelodeon Board Shorts (view 1)Price Drop
    View Product: Nickelodeon Board Shorts

    Nickelodeon

    Board Shorts
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    18% off estimated retail
    Carter's Rash Guard (view 2)Carter's Rash Guard (view 1)Price Drop
    View Product: Carter's Rash Guard

    Carter's

    Rash Guard
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    65% 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 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    42% off estimated retail
    Absorba Board Shorts (view 2)Absorba Board Shorts (view 1)Price Drop
    View Product: Absorba Board Shorts

    Absorba

    Board Shorts
    Size 3-6 mo
    $6.99 $5.59 20% off with code HOTDEAL
    36% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)Price Drop
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    56% off estimated retail
    Cat & Jack Board Shorts (view 2)Cat & Jack Board Shorts (view 1)Price Drop
    View Product: Cat & Jack Board Shorts

    Cat & Jack

    Board Shorts
    Size 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    23% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)Price Drop
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    56% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)Price Drop
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    56% off estimated retail
    Disney Rash Guard (view 2)Disney Rash Guard (view 1)Price Drop
    View Product: Disney Rash Guard

    Disney

    Rash Guard
    Size 3-6 mo
    $6.99 $5.59 20% off with code HOTDEAL
    36% 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 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    57% off estimated retail
    Unbranded Rash Guard (view 2)Unbranded Rash Guard (view 1)Price Drop
    View Product: Unbranded Rash Guard

    Unbranded

    Rash Guard
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    59% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)Price Drop
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    56% off estimated retail
    First Impressions Board Shorts (view 2)First Impressions Board Shorts (view 1)Price Drop
    View Product: First Impressions Board Shorts

    First Impressions

    Board Shorts
    Size 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    44% off estimated retail
    Cat & Jack Rash Guard (view 2)Cat & Jack Rash Guard (view 1)Price Drop
    View Product: Cat & Jack Rash Guard

    Cat & Jack

    Rash Guard
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    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 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    57% off estimated retail
    OshKosh B'gosh Rash Guard (view 2)OshKosh B'gosh Rash Guard (view 1)Price Drop
    View Product: OshKosh B'gosh Rash Guard

    OshKosh B'gosh

    Rash Guard
    Size 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    54% 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 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    28% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)Price Drop
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    56% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)Price Drop
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    60% 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 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    42% 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 3-6 mo
    $9.99 $7.99 20% off with code HOTDEAL
    52% 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 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    35% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)Price Drop
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    66% off estimated retail
    Boyz Board Shorts (view 2)Boyz Board Shorts (view 1)
    View Product: Boyz Board Shorts

    Boyz

    Board Shorts
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    11% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)Price Drop
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    68% off estimated retail
    Carter's Rash Guard (view 2)Carter's Rash Guard (view 1)
    View Product: Carter's Rash Guard

    Carter's

    Rash Guard
    Size 3-6 mo
    $8.99 $7.19 20% off with code HOTDEAL
    62% off estimated retail
    Lands' End Board Shorts (view 2)Lands' End Board Shorts (view 1)Price Drop
    View Product: Lands' End Board Shorts

    Lands' End

    Board Shorts
    Size 3-6 mo
    $7.99 $6.39 20% off with code HOTDEAL
    42% off estimated retail
    Gymboree Board Shorts (view 2)Gymboree Board Shorts (view 1)
    View Product: Gymboree Board Shorts

    Gymboree

    Board Shorts
    Size 3-6 mo
    $6.99 $5.59 20% off with code HOTDEAL
    72% 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 3-6 mo
    $6.99 $5.59 20% off with code HOTDEAL
    46% 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 3-6 mo
    $6.99 $5.59 20% off with code HOTDEAL
    46% off estimated retail
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