Not all bra brands cover the same range of sizes or uses. Some create complete ranges up to deep cups, others stop at a D cup, while some specialise in sports or breastfeeding. It's this speciality, more than style, that should guide your choice.
Three criteria come before aesthetics. First is the depth of the range: a brand that offers the same line from size A to size H allows you to keep your model while changing sizes. Next is the consistency of sizing: a brand whose fit doesn't change from one collection to another means you don't have to try everything on again each season. Finally, specialisation, as some brands have built their reputation on specific segments, such as sports bras, breastfeeding, or very large cups: this is where you'll find large size bra brands, and higher up the range, premium bra brands.
The same advertised size may not deliver the same volume depending on the brand, as the fit can vary by several millimetres in the cup. A useful instinct is to think in terms of sister sizes rather than sticking to a number: if your usual size feels loose in a new bra brand, try going down a letter and up a band size before deciding that the fit doesn’t suit you.
For deep cups, Anita, Freya, Fantasie and Elomi cover sizes that most brands drop at D cup. For everyday comfort, Triumph, Wacoal and Passionata each rely on corsetry patterns, with the first being Japanese and the last French. Conte Elegant and Lisca come from knitted fabrics and Central Europe, while Esotiq hails from Poland, offering an unusual level of lace at this price point. Selmark maintains affordability across a full range, while Morgan and Pomm'Poire approach bras more from a fashion angle than a technical one.