Plus Size Tankini Swimsuits Market Report: Sales Volume, Market Share, Leading Brands & Market Trends

Daci is the best-performing plus size tankini swimsuits brand in July 2026, moving 1,600 units across 2 ASINs for 28.6% of Top 10 volume. Summer Mae follows with 900 units (16.1%), ahead of MODLILY on 800 units (14.3%).

Volume is spread across 7 brands, with the top three holding 58.9% between them. No single label controls the shelf, which usually leaves room for a well-differentiated listing to take share without outspending an incumbent. Average selling prices among the leaders run from $39.99 to $44.54, 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, 2 ASINs forced its way in: B0DNHNBFG9 booked 400 units at $29.20, with ▲ 0.0% MoM change. On the growth side, B09S8L7P3S leads positive momentum with ▲ 100.0% MoM growth on 100 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already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date.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.