Multi-region, US vs UK vs EU bra sizing politics, anything else to know?

Beyond the cup-volume incompatibility (covered earlier), three more multi-region quirks bite lingerie brands hard:

• Regional sizing taboos. EU customers expect cm-based bands; printing only inch-based labels on EU store views reads as “they don’t actually sell to us.” AU expects band 8 / 10 / 12 / 14 / 16 (corresponding to UK 30 / 32 / 34 / 36 / 38). Translating wrong is worse than not translating.
• Currency + tax-inclusive pricing. EU requires VAT-included display prices (a UK customer seeing £30 should see £30 at checkout, not £30 + 20% VAT). US is tax-exclusive (price at checkout adds state tax). Magento store views handle this natively via tax-class + display-price-inclusive settings per store view; Shopify Markets is more constrained.
• Returns shipping costs. Cross-border returns are brutal for lingerie, a 40% return rate at $25 return-shipping per package crushes margin. Pattern that works: regional return hubs (US returns to a US hub, EU returns to a Netherlands hub, UK returns to a UK hub). Stock is then redistributed back via slower freight. Loop Returns + Aftership both support regional hub routing.
• Compliance: textile labeling. EU requires fiber composition labels in 22 languages on the garment. US requires country-of-origin + RN/WPL number. UK requires CE marking for compression shapewear. Some of this is fulfillment-side, but the PDP needs to surface the right info per region (composition first in EU, country-of-origin first in US).

Magento + MSI (Multi-Source Inventory, native since 2.3) handles the warehouse routing piece; store views handle currency + pricing + labels. The combination is why lingerie brands above $5M GMV with multi-region ambition usually land on Magento.