Size 30G Bikinis

A 30G bikini top is a rare find — the combination of a small 30 band with a G cup depth is virtually nonexistent in mainstream retail. But if you know you're a 30G, you also know that guessing at standard sizing means sacrificing either band fit or cup coverage. A true 30G bikini top respects both measurements: a firm band that doesn't ride or twist, and cups engineered with the projection, shaping, and seaming that a fuller cup requires. When everything fits correctly, you stop thinking about your swimwear and start actually enjoying the water.

Bikini Style Recommendations for 30G

At 30G, underwired or molded bikini tops are your best foundation — they provide the structural support that a fuller cup demands and prevent sagging or loss of shape. Look for styles with reinforced side seaming that extends the full height of the cup; this prevents spillage at the sides and ensures smooth lines under a cover-up. Full-cup designs tend to work better than balconette or half-cup styles, which can create spillage at the top. The band should have minimal stretch and be cut true to 30 inches — a stretched band defeats the support you're seeking. Multi-seam cup construction (rather than single-piece cups) gives you the shaping and control that larger cup depths require. Prioritize durability in fabric weight, as larger cups put more demand on materials.

Cup-Sized Bikinis, Curated by Fit Experts

At The Bra Diva, we carry bikinis the same way we carry bras — by actual bra size, not just by small, medium, or large. Every style in this collection is selected for its construction quality, true-to-size fit, and ability to hold up in and out of the water. Our team has been fitting customers since 1987 at our Cherry Hill, NJ boutique, and we bring that same expertise to every size we carry online.

Shopping for more styles in size 30G? Browse our Size 30G Swimwear collection, or shop Size 30G Bras for everyday lingerie in your size.

Not sure if 30G is your correct size? Use our bikini size chart →