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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.

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91 items
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    Assorted Brands Wetsuit (view 2)Assorted Brands Wetsuit (view 1)
    View Product: Assorted Brands Wetsuit

    Assorted Brands

    Wetsuit
    Size 9-12 mo
    $19.99
    54% off estimated retail
    Hanna Andersson Rash Guard (view 2)Hanna Andersson Rash Guard (view 1)
    View Product: Hanna Andersson Rash Guard

    Hanna Andersson

    Rash Guard
    Size 110 cm
    $19.99
    51% off estimated retail
    Hanna Andersson Rash Guard (view 2)Hanna Andersson Rash Guard (view 1)
    View Product: Hanna Andersson Rash Guard

    Hanna Andersson

    Rash Guard
    Size 5
    $22.99
    43% off estimated retail
    The Beaufort Bonnet Company Board Shorts (view 2)The Beaufort Bonnet Company Board Shorts (view 1)
    View Product: The Beaufort Bonnet Company Board Shorts

    The Beaufort Bonnet Company

    Board Shorts
    Size 5
    $23.99
    46% off estimated retail
    The Edit. Forever Classic, Get perfectly polished in trousers, blazers, and more. Shop The Edit
    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 7
    $8.99
    57% off estimated retail
    Nununu Rash Guard (view 2)Nununu Rash Guard (view 1)
    View Product: Nununu Rash Guard

    Nununu

    Rash Guard
    Size 4
    $16.99
    58% 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
    REI Rash Guard (view 2)REI Rash Guard (view 1)
    View Product: REI Rash Guard

    REI

    Rash Guard
    Size X-Small kids
    $11.99
    64% off estimated retail
    Baby Gap Rash Guard (view 2)Baby Gap Rash Guard (view 1)
    View Product: Baby Gap Rash Guard

    Baby Gap

    Rash Guard
    Size 18-24 mo
    $13.99
    33% off estimated retail
    Baby Gap Rash Guard (view 2)Baby Gap Rash Guard (view 1)
    View Product: Baby Gap Rash Guard

    Baby Gap

    Rash Guard
    Size 18-24 mo
    $10.99
    47% 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 Large youth
    $14.99
    54% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 3
    $12.99
    43% off estimated retail
    Leveret Rash Guard (view 2)Leveret Rash Guard (view 1)
    View Product: Leveret Rash Guard

    Leveret

    Rash Guard
    Size 18-24 mo
    $12.99
    51% off estimated retail
    Gap Board Shorts (view 2)Gap Board Shorts (view 1)
    View Product: Gap Board Shorts

    Gap

    Board Shorts
    Size X-Small youth
    $12.99
    60% off estimated retail
    Marvel Rash Guard (view 2)Marvel Rash Guard (view 1)
    View Product: Marvel Rash Guard

    Marvel

    Rash Guard
    Size 5
    $12.99
    51% 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 Wetsuit (view 2)Baby Gap Wetsuit (view 1)Flawed Gem
    View Product: Baby Gap Wetsuit

    Baby Gap

    Wetsuit
    Size 18-24 mo
    $11.99
    42% 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 18-24 mo
    $8.99
    43% off estimated retail
    Lands' End Rash Guard (view 2)Lands' End Rash Guard (view 1)
    View Product: Lands' End Rash Guard

    Lands' End

    Rash Guard
    Size 5
    $11.99 $7.79 35% off with code SHINE
    63% off estimated retail
    Crewcuts Rash Guard (view 2)Crewcuts Rash Guard (view 1)
    View Product: Crewcuts Rash Guard

    Crewcuts

    Rash Guard
    Size 5
    $13.99 $9.79 30% off with code SHINE
    65% off estimated retail
    Baby Wear Rash Guard (view 2)Baby Wear Rash Guard (view 1)New With Tags
    View Product: Baby Wear Rash Guard

    Baby Wear

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

    Onia

    Board Shorts
    Size 12 mo
    $15.99 $11.99 25% off with code SHINE
    68% off estimated retail
    Hanna Andersson Wetsuit (view 2)Hanna Andersson Wetsuit (view 1)
    View Product: Hanna Andersson Wetsuit

    Hanna Andersson

    Wetsuit
    Size 80 cm
    $21.99 $14.29 35% off with code SHINE
    50% off estimated retail
    Hanna Andersson Rash Guard (view 2)Hanna Andersson Rash Guard (view 1)
    View Product: Hanna Andersson Rash Guard

    Hanna Andersson

    Rash Guard
    Size 70 cm
    $18.99 $11.39 40% off with code SHINE
    53% off estimated retail
    I Play Rash Guard (view 2)I Play Rash Guard (view 1)
    View Product: I Play Rash Guard

    I Play

    Rash Guard
    Size 6 mo
    $9.99 $7.99 20% off with code SHINE
    $11
    Unbranded Board Shorts (view 2)Unbranded Board Shorts (view 1)
    View Product: Unbranded Board Shorts

    Unbranded

    Board Shorts
    Size 12 mo
    $6.99 $5.59 20% off with code SHINE
    53% off estimated retail
    Lands' End Rash Guard (view 2)Lands' End Rash Guard (view 1)
    View Product: Lands' End Rash Guard

    Lands' End

    Rash Guard
    Size Medium kids
    $12.99 $9.09 30% off with code SHINE
    51% 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 18 mo
    $7.99 $6.39 20% off with code SHINE
    55% off estimated retail
    Gap Kids Rash Guard (view 2)Gap Kids Rash Guard (view 1)
    View Product: Gap Kids Rash Guard

    Gap Kids

    Rash Guard
    Size 4
    $12.99 $9.74 25% off with code SHINE
    51% 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
    Assorted Brands Wetsuit (view 2)Assorted Brands Wetsuit (view 1)
    View Product: Assorted Brands Wetsuit

    Assorted Brands

    Wetsuit
    Size X-Large youth
    $28.99 $21.74 25% off with code SHINE
    55% off estimated retail
    Quiksilver Rash Guard (view 2)Quiksilver Rash Guard (view 1)
    View Product: Quiksilver Rash Guard

    Quiksilver

    Rash Guard
    Size 6 mo
    $10.99 $8.24 25% off with code SHINE
    50% off estimated retail
    Volcom Rash Guard (view 2)Volcom Rash Guard (view 1)
    View Product: Volcom Rash Guard

    Volcom

    Rash Guard
    Size 4T
    $14.99 $9.74 35% off with code SHINE
    55% 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 Rash Guard (view 2)Janie and Jack Rash Guard (view 1)
    View Product: Janie and Jack Rash Guard

    Janie and Jack

    Rash Guard
    Size 6-12 mo
    $14.99 $10.49 30% off with code SHINE
    51% off estimated retail
    True Religion Rash Guard (view 2)True Religion Rash Guard (view 1)
    View Product: True Religion Rash Guard

    True Religion

    Rash Guard
    Size 3T
    $17.99 $12.59 30% off with code SHINE
    78% off estimated retail
    True Religion Rash Guard (view 2)True Religion Rash Guard (view 1)
    View Product: True Religion Rash Guard

    True Religion

    Rash Guard
    Size 3T
    $17.99 $12.59 30% off with code SHINE
    78% off estimated retail
    Dakine Rash Guard (view 2)Dakine Rash Guard (view 1)
    View Product: Dakine Rash Guard

    Dakine

    Rash Guard
    Size 4T
    $26.99 $17.54 35% off with code SHINE
    60% 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
    Billabong Rash Guard (view 2)Billabong Rash Guard (view 1)
    View Product: Billabong Rash Guard

    Billabong

    Rash Guard
    Size 2
    $14.99 $9.74 35% off with code SHINE
    72% off estimated retail
    Assorted Brands Wetsuit (view 2)Assorted Brands Wetsuit (view 1)
    View Product: Assorted Brands Wetsuit

    Assorted Brands

    Wetsuit
    Size Medium kids
    $27.99 $20.99 25% off with code SHINE
    56% off estimated retail
    Assorted Brands Wetsuit (view 2)Assorted Brands Wetsuit (view 1)
    View Product: Assorted Brands Wetsuit

    Assorted Brands

    Wetsuit
    Size X-Large youth
    $28.99 $21.74 25% off with code SHINE
    55% 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
    Reel Legends Board Shorts (view 2)Reel Legends Board Shorts (view 1)
    View Product: Reel Legends Board Shorts

    Reel Legends

    Board Shorts
    Size Medium kids
    $6.99 $5.59 20% off with code SHINE
    $7
    Pro Spirit Wetsuit (view 2)Pro Spirit Wetsuit (view 1)
    View Product: Pro Spirit Wetsuit

    Pro Spirit

    Wetsuit
    Size Large youth
    $11.99 $7.79 35% off with code SHINE
    63% off estimated retail
    Baby Gap Outlet Rash Guard (view 2)Baby Gap Outlet Rash Guard (view 1)
    View Product: Baby Gap Outlet Rash Guard

    Baby Gap Outlet

    Rash Guard
    Size 6 mo
    $9.99 $7.99 20% off with code SHINE
    $11
    Assorted Brands Rash Guard (view 2)Assorted Brands Rash Guard (view 1)
    View Product: Assorted Brands Rash Guard

    Assorted Brands

    Rash Guard
    Size Medium tots
    $10.99 $8.79 20% off with code SHINE
    66% off estimated retail
    I Play Rash Guard (view 2)I Play Rash Guard (view 1)
    View Product: I Play Rash Guard

    I Play

    Rash Guard
    Size 18 mo
    $6.99 $5.59 20% off with code SHINE
    36% off estimated retail
    I Play Rash Guard (view 2)I Play Rash Guard (view 1)
    View Product: I Play Rash Guard

    I Play

    Rash Guard
    Size 6 mo
    $9.99 $7.99 20% off with code SHINE
    $11
    Hanna Andersson Rash Guard (view 2)Hanna Andersson Rash Guard (view 1)
    View Product: Hanna Andersson Rash Guard

    Hanna Andersson

    Rash Guard
    Size 70 cm
    $23.99 $13.19 45% off with code SHINE
    41% 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 $10.00 50% off with code SHINE
    33% off estimated retail
    Baby Gap Rash Guard (view 2)Baby Gap Rash Guard (view 1)
    View Product: Baby Gap Rash Guard

    Baby Gap

    Rash Guard
    Size Newborn
    $11.99 $9.59 20% off with code SHINE
    42% 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 0-3 mo
    $7.99 $6.39 20% off with code SHINE
    42% 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 $8.99 25% off with code SHINE
    47% off estimated retail
    Lazoo Rash Guard (view 2)Lazoo Rash Guard (view 1)
    View Product: Lazoo Rash Guard

    Lazoo

    Rash Guard
    Size 18 mo
    $6.99 $5.59 20% off with code SHINE
    36% 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 12 mo
    $14.99 $10.49 30% off with code SHINE
    50% off estimated retail
    Gymboree Rash Guard (view 2)Gymboree Rash Guard (view 1)
    View Product: Gymboree Rash Guard

    Gymboree

    Rash Guard
    Size 6-12 mo
    $11.99 $8.99 25% off with code SHINE
    47% 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
    Hanna Andersson Rash Guard (view 2)Hanna Andersson Rash Guard (view 1)Price Drop
    View Product: Hanna Andersson Rash Guard

    Hanna Andersson

    Rash Guard
    Size 70 cm
    $20.99 $11.54 45% off with code SHINE
    48% off estimated retail
    Assorted Brands Wetsuit (view 2)Assorted Brands Wetsuit (view 1)Price Drop
    View Product: Assorted Brands Wetsuit

    Assorted Brands

    Wetsuit
    Size 20
    $24.99 $19.99 20% off with code SHINE
    61% off estimated retail
    Assorted Brands Wetsuit (view 2)Assorted Brands Wetsuit (view 1)Price Drop
    View Product: Assorted Brands Wetsuit

    Assorted Brands

    Wetsuit
    Size 20
    $25.99 $20.79 20% off with code SHINE
    60% off estimated retail
    Assorted Brands Wetsuit (view 2)Assorted Brands Wetsuit (view 1)Price Drop
    View Product: Assorted Brands Wetsuit

    Assorted Brands

    Wetsuit
    Size 20
    $24.99 $19.99 20% off with code SHINE
    61% 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 SHINE
    71% 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 6 mo
    $7.99 $6.39 20% off with code SHINE
    66% 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 9 mo
    $10.99 $8.24 25% off with code SHINE
    57% 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 SHINE
    65% 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 12 mo
    $8.99 $7.19 20% off with code SHINE
    70% off estimated retail
    Hatley Rash Guard (view 2)Hatley Rash Guard (view 1)Price Drop
    View Product: Hatley Rash Guard

    Hatley

    Rash Guard
    Size 9-12 mo
    $10.99 $7.69 30% off with code SHINE
    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 $7.49 25% off with code SHINE
    56% off estimated retail
    Carter's Board Shorts (view 2)Carter's Board Shorts (view 1)Price Drop
    View Product: Carter's Board Shorts

    Carter's

    Board Shorts
    Size 18 mo
    $9.99 $7.99 20% off with code SHINE
    61% 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 6-12 mo
    $9.99 $7.99 20% off with code SHINE
    54% 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 Small infants
    $6.99 $5.59 20% off with code SHINE
    50% 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 18
    $8.99 $7.19 20% off with code SHINE
    70% 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 6 mo
    $9.99 $7.99 20% off with code SHINE
    61% 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 SHINE
    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 SHINE
    56% 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 mo
    $9.99 $7.49 25% off with code SHINE
    61% 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
    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 SHINE
    56% 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 mo
    $8.99 $7.19 20% off with code SHINE
    65% 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 80 cm
    $9.99 $7.99 20% off with code SHINE
    54% 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 6 mo
    $8.99 $7.19 20% off with code SHINE
    65% off estimated retail
    OshKosh B'gosh Board Shorts (view 2)OshKosh B'gosh Board Shorts (view 1)Price Drop
    View Product: OshKosh B'gosh Board Shorts

    OshKosh B'gosh

    Board Shorts
    Size 18 mo
    $8.99 $7.19 20% off with code SHINE
    52% 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 9 mo
    $8.99 $7.19 20% off with code SHINE
    59% 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 3 mo
    $8.99 $7.19 20% off with code SHINE
    57% 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 6 mo
    $8.99 $7.19 20% off with code SHINE
    62% 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 6 mo
    $8.99 $7.19 20% off with code SHINE
    62% 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 18 mo
    $8.99 $7.19 20% off with code SHINE
    57% 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 6 mo
    $8.99 $7.19 20% off with code SHINE
    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 SHINE
    42% off estimated retail
    Little Me Rash Guard (view 2)Little Me Rash Guard (view 1)
    View Product: Little Me Rash Guard

    Little Me

    Rash Guard
    Size 12 mo
    $8.99 $7.19 20% off with code SHINE
    40% off estimated retail
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