Quick answer
Visible lines under a T-shirt are usually caused by a bra that doesn't fit your ribcage snugly or has seams that press through thin fabric. The fix starts with diagnosing the type of line you see.
Why lines appear even with a "seamless" bra
A bra labeled seamless still has edges—underwires, straps, and the band closure—that can press into your skin and show through knit fabrics. If the band is too loose, it shifts and creates horizontal ridges. If the cups are too small, the underwire digs in and leaves a visible outline. Fabric also matters: thin cotton or ribbed knits cling more than thicker jersey or textured weaves.
When a different style might work better
Some T-shirts are simply too thin or clingy for any bra with an underwire. In that case, a bralette or adhesive cup could be a better option. But if you prefer support and shape, a molded underwire cup with bonded edges—like the Le Gloss T-Shirt Bra—is designed to minimize visible lines because the wings are seamless and the straps are adjustable silk, which lies flatter than standard elastic.
Diagnose & fix your bra lines
- Symptom: Horizontal lines across the back: The band is too loose and riding up. Tighten to the loosest hook that stays level, or try a smaller band size.
- Symptom: Vertical lines at the sides of the cups: The underwire is sitting on breast tissue, not the ribcage. Size up in the cup or switch to a style with a wider wire channel.
- Symptom: Shoulder strap lines: Straps are too tight or too wide. Loosen them slightly; if the bra still feels unsupported, the band may be too loose. Silk straps (like on Le Gloss) tend to stay in place without digging in. If none of these adjustments eliminate the lines, the shirt fabric may be too thin for any underwire bra. Consider a seamless bralette or adhesive cup instead.
Product that helps
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Le Gloss T-Shirt Bra: Molded underwire cups with seamless bonded wings and adjustable silk straps. Bonded wings eliminate the side seams that often create ridges, and silk straps sit flatter than standard elastic, reducing shoulder lines.
Le Gloss T-Shirt Bra
