Mermaid Party Decorations Market Report: Sales Volume, Market Share, Leading Brands & Market Trends

GREATRIL is the best-performing mermaid party decorations brand in July 2026, moving 11,000 units across 2 ASINs for 23.4% of Top 10 volume. MEICOLY follows with 10,000 units (21.3%), ahead of BOMSI on 9,000 units (19.1%).

With 9 brands splitting the Top 10 and 63.8% 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 $5.99 to $11.33, 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: B0CKBD8W1Q booked 2K units at $7.99, with ▲ 100.0% MoM change. On the growth side, B0GXXYNLQD leads positive momentum with ▲ 300.0% MoM growth on 400 units, with B0GTNX9D96 close behind at ▲ 233.3% MoM on 1K 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already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date.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.