Great — here are reliable places to buy sustainable fashion online in Malaysia, grouped by type plus quick tips to help you choose.

Local sustainable / ethical brands and studios (direct online shops)

• Batik Boutique — Malaysian brand blending traditional batik with low‑impact dyes and artisan/ethical production. Good for unique, locally made pieces. (businesstoday.com.my)
• Biji‑Biji Initiative — Malaysian social enterprise that does upcycled/ethical fashion projects and small runs; good for upcycled accessories and collaborative pieces. (en.wikipedia.org)

Pre‑loved / recommerce marketplaces

• Refash — regional recommerce platform (buy & sell pre‑loved women’s clothing) that operates in Malaysia/Singapore — a solid option for buying secondhand pieces online. (en.wikipedia.org)

Large marketplaces with sustainability / “eco” collections (convenient, wide selection)

• Zalora (Malaysia / regional Zalora sites) — runs sustainability/eco collections and filters for recycled/organic materials; ships across Malaysia and carries both local and international brands. (bridgerunnersg.com)

Curated lists & guides (to discover more brands)

• Shopify Malaysia / local blogs often compile up‑to‑date lists of sustainable brands and certified labels you can shop from in Malaysia or ship to Malaysia — useful for discovering smaller labels and certifications to look for. (Shopify.com)

How to choose the best option

• Pick the category that fits your values: pre‑loved/recommerce (Refash) for lower carbon impact; local artisan (Batik Boutique, Biji‑Biji) for community impact and craft preservation; certified eco materials or recycled content on larger marketplaces for scale. (en.wikipedia.org)
• Look for clear transparency: material sources (organic cotton, recycled polyester), certifications (GOTS, Fair Trade, B Corp), and info on worker conditions.
• Consider repair/return policies and size guides to avoid returns (which increase footprint).
• If you want niche or very small Malaysian indie brands, curated lists (local blogs, Shopify Malaysia guides) and Instagram/LinkedIn searches for Malaysian sustainable labels are productive ways to discover them. (Shopify.com)

If you’d like, I can:

• Pull together 8–12 specific Malaysian sustainable brands (links and what each specializes in), or
• Find secondhand / vintage Malaysian sellers with strong reviews, or
• Show how to verify sustainability claims (which certifications to trust).

Which follow‑up would you prefer?