Underwear Seamless Market Report: Sales Volume, Market Share, Leading Brands & Market Trends

INNERSY is the best-performing underwear seamless brand in July 2026, moving 14,000 units across 2 ASINs for 24.6% of Top 10 volume. Caterlove follows with 10,000 units (17.5%), ahead of FINETOO on 8,000 units (14.0%).

Volume is spread across 8 brands, with the top three holding 56.1% 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 $9.99 to $14.99, 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: B0D9H4KJK8 booked 4K units at $14.99, with ▲ 33.3% MoM change. On the growth side, B0G2QTN3VB leads positive momentum with ▲ 122.2% MoM growth 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already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date.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.