Seamless Bras: What You Need to Know if You’re Full-Busted

A seamless bra, often called a t-shirt bra, features a cup without seams and is made from a single piece of moulded fabric or polyurethane foam, including spacer foam. These bras are loved for their smooth appearance under clothing, but they may not be the best fit for every bust shape, especially if you're in the DD+ size range.

How Seamless Bras Are Made

Using heat and pressure, a flat piece of fabric or foam is moulded to create a 3D cup shape. Due to the limitations of moulds and the properties of fabrics, there’s often a cap on how large a cup can be created using moulding technology. This can lead to a compromise in fit and shaping for those with a full bust or projected breasts.

An assortment of cup moulds at an Indonesian bra manufacturer used to create t-shirt bras in various sizes.

Seamless vs. Cut and Sewn Bras: What's the Difference?

With the absence of seams to direct and shape the bust, a seamless cup won’t offer the same support or lift as a cut and sewn bra (a bra with sewn seams). Seamless t-shirt bras tend to create a rounded shape but often lack structure, especially for larger cup sizes.

From Left to Right: Panache 365 T-Shirt Bra, Freya Deco, and Freya Idol—three popular moulded bras for larger busts.

Why Moulded Foam Cups Can Gap

Many people experience gaping at the neckline or empty space at the top of the cup in moulded foam bras. This usually comes down to a shape mismatch. Moulded cups are fixed in shape, and breasts aren't. Pendulous or projected breasts often struggle with moulded cups, which tend to be wide and shallow.

If you’ve ever asked, “Why does my bra cup gap at the top?”—you’re not alone.

From Left to Right: PrimaDonna Madison, PrimaDonna Satin, and Fantasie Demure—supportive seamless bras for DD+ sizes.

Spacer Foam: A More Flexible Seamless Option

Spacer foam cups offer more flexibility due to the stretch and breathability of the foam. This makes them a better option for a variety of breast shapes, especially if you need a t-shirt bra that fits uneven or full-on-top breasts.

Left to Right: Elomi Charley Spacer, Fantasie Envisage Spacer and Corin Virginia Spacer—three breathable spacer bras ideal for everyday wear.

Some of our favourite seamless bras for full busts include:

• PrimaDonna Madison (moulded lace)

• Elomi Charley Spacer

• Fantasie Envisage Spacer

Final Thoughts: Finding a Seamless Bra That Fits

You're not alone in the struggle to find the perfect t-shirt bra for a full bust. At Kimtimates, we carry a broad range of seamless and spacer bras in cup sizes DD – H (UK) and E – J (EU), and we can help you find the right style for your unique shape, whether you're dealing with cup gaping, nipple show-through, or support issues.

Need help finding the best t-shirt bra for your body? Come in for a personalized fitting or message us with your questions. Let’s make sure your next seamless bra actually feels seamless.

Kimtimates | The Bra Fit Specialists

Have a good fit.