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

G Gradual is the best-performing oneill women swim brand in July 2026, moving 3,700 units across 2 ASINs for 45.1% of Top 10 volume. CUPSHE follows with 2,400 units (29.3%), ahead of HODOSPORTS on 900 units (11.0%).

With 5 brands splitting the Top 10 and 85.4% 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 $19.98 to $36.74, 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. On the growth side, B0FYNQ9QR4 leads positive momentum with ▲ 300.0% MoM growth on 200 units, with B0GQ9C7CXY close behind at ▲ 100.0% MoM on 200 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already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date.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.