Swim Shirt Market Report: Sales Volume, Market Share, Leading Brands & Market Trends

MAGCOMSEN is the best-performing swim shirt brand in July 2026, moving 6,000 units across 3 ASINs for 30.0% of Top 10 volume. G Gradual follows with 4,000 units (20.0%), ahead of Dalavch on 3,000 units (15.0%).

With 6 brands splitting the Top 10 and 65.0% of volume sitting with three of them, this is a concentrated shelf — the leaders hold multiple listings or one very high-velocity ASIN, so a new entrant competes against established review moats rather than an open field. Average selling prices among the leaders run from $11.99 to $19.88, which frames the price band a competing listing has to justify.

Based on July 2026 data, this shortlist surfaces the two kinds of ASIN worth keeping an eye on — the ones that just broke into the Top 10, and the ones growing fastest month over month. Specifically, one ASIN forced its way in: B072BMXDRC booked 1K units at $14.24, with ▲ 11.1% MoM change. On the growth side, B0DPGR3MRK leads positive momentum with ▲ 150.0% MoM growth on 500 units, with B071RYCHPK close behind at ▲ 100.0% MoM on 2K units.

The two signals carry different weight. A fresh entrant means share has already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date. A steep growth rate works as the earlier warning: it marks demand that is still compounding, usually a month or two before the ranking catches up to it.