Underwire one-pieces are worth it.

Yes, if you want actual support and shape from a one-piece, underwire is the move.

Most one-pieces rely on compression — they just squish everything down. Underwire lifts and separates, which is more comfortable for larger chests and keeps things where they belong when you’re swimming or playing with kids. The straps stay on your shoulders, and you’re not constantly adjusting.

The trade-off is that underwire swimsuits dry slower (wire channels hold water), and you need to rinse them well after chlorine or salt. But for all-day wear or active beach days, the support difference is massive.