SwimHer
What they make
Extended-size tween & teen swim only
- Designed only for the tween/teen size gap
- Age-appropriate coverage, real body inclusivity
- Tankinis, one-pieces, mix-and-match tops/bottoms
- One brand's styles; small-batch, can sell out
Plus size swimwear for tweens and teens, without the “sold out” hunt
Curvy tweens and teens fall into a real gap: too big for the kids' racks, not ready for women's sizes. These are the brands that actually cut swimwear for that in-between body, with notes on how each one fits and links straight to live stock.
Short answer, the most reliable brands right now:
SwimHer (specialist), Lands' End, Lime Ricki (modest), and the big-box plus lines at Target and Walmart.
Prefer more coverage? We flag modest, higher-coverage styles (rash guards, swim shorts, full one-pieces) on every list.
Brands that actually make it
From a specialist that designs only for this gap, to the big-box plus lines that restock all summer.
Lands' End
Hidden category
Girls' Plus + Women's Plus (1X–3X)
- Bridges girls' plus straight into women's plus
- True UPF 50, long torso, modest coverage
- Mix-and-match tankini tops & bottoms by size
- Classic styling; higher price
Lime Ricki
Hidden category
Women's modest, fits older / taller tweens
- Modest, higher-coverage cuts and swim shorts
- Smallest women's sizes fit older tweens
- Mix-and-match tops and bottoms
- Premium price; top sizes sell out early
Cabana Life
Hidden category
Girls' UPF 50+ rash-guard sets
- Full-coverage sun protection, longer cuts
- Great for taller tweens and active swimmers
- Crossover into beach activewear
- Premium price; sizes cap early, check the chart
Target
Hidden category
Cat & Jack Girls' Plus + women's XS pivot
- Cheap, wide availability, true Plus cut
- Women's XS works for tall, slim teens
- Matching All in Motion activewear
- Best sizes sell out online by mid-June
Walmart
Hidden category
Wonder Nation Girls Plus (7–18)
- Lowest price; in stock most of the season
- Dedicated Girls Plus line + coverups
- Matching Wonder Nation Active pieces
- Thinner fabric; fit varies by style
Amazon
Hidden category
“Plus size swimsuit for tweens” (filter by size)
- Biggest selection; dozens of plus & UPF brands
- Fast Prime delivery before a trip
- Easy to filter by size and read recent reviews
- Seller sizing varies; check reviews before buying
Buttons open each brand's live results in a new tab. We don't hold inventory; prices and stock are set by each store and change constantly.
How plus tween & teen sizing works
There are three size systems hiding behind “plus,” and knowing which one she's in saves a lot of returns.
1. Girls' Plus (numeric 14 to 20)
Same kid height, fuller cut through chest, tummy and hip. Best for a curvy tween who still has a shorter torso. This is where Target, Walmart and Lands' End live.
2. Juniors / Women's Plus (1X to 3X)
Longer torso, more bust shaping, made for an older or developed teen. SwimHer and Lands' End bridge into this range.
3. Women's XS / S (the tall-slim pivot)
For a tall, slim teen who has simply outgrown girls' lengths. A women's XS often fits better than forcing a girls' top size.
Always go by chest, waist and hip measurements, not age. For the exact size-18 numbers across brands, see the girls size 18 sizing chart.
Plus tween & teen swim: questions answered
What sizes count as “plus” for a tween or teen?
For tweens and teens, plus usually means girls' numeric 14 to 20 cut with extra room (often tagged Plus), then juniors or women's 1X to 3X. Some brands also use a women's XS or S for a tall, slim teen who has outgrown girls' sizing. Go by chest, waist and hip measurements rather than age.
Is junior plus the same as girls plus?
Not quite. Girls' plus keeps a shorter, kid-proportioned torso with less bust shaping, while junior plus is cut longer with more shaping for an older teen body. A curvy tween often fits girls' plus best; an older or developed teen usually fits junior plus or women's sizing better.
Where can I find modest plus-size swimwear for teens?
Lime Ricki and Lands' End both make higher-coverage, modest plus options (longer tops, swim shorts, full-coverage one-pieces), and SwimHer designs age-appropriate coverage specifically for tweens and teens. Rash-guard sets from Cabana Life also give full sleeves plus sun protection.
What if she is between girls' and women's sizes?
This is the most common tween gap. If a girls' top size fits in length but is tight through the chest or tummy, size into a girls' Plus cut. If she has the height and shape of a teen, pivot to a women's XS or S, or a junior plus. Tankinis help because you can size the top and bottom separately.
Do these brands make matching activewear?
Yes. Plus-size tween activewear follows the same numeric chart as swim, so Target's All in Motion, Walmart's Wonder Nation Active and Lands' End all carry matching leggings and sports pieces. See our plus size activewear guide for the details.