Short answer

• For most shoppers in Singapore who value faster delivery, easier returns, local warranties and more reliable sizing/quality, Zalora is better.
• For buyers prioritizing the lowest prices and the largest variety of ultra-fast trends (at the cost of longer shipping, variable quality, and trickier returns), SHEIN is better.

Why (factor-by-factor)

• Selection and trends

  • SHEIN: enormous inventory of ultra-fast-fashion, lots of very cheap trend pieces and frequent new arrivals.
  • Zalora: broad selection too, but skewed toward curated brands (local & international), higher-end options and multi-brand assortment.

• Price

  • SHEIN: generally cheaper for basics and trend pieces. Discounts and flash sales common.
  • Zalora: pricier on average but runs frequent promotions and carries mid/upper-tier brands you won’t find on SHEIN.

• Quality & sizing consistency

  • SHEIN: quality varies widely by item and seller; sizing is inconsistent across products—read reviews & check measurements.
  • Zalora: better overall consistency, especially for known brands; easier to trust sizing and product descriptions.

• Shipping & delivery

  • SHEIN: many items ship from overseas; longer delivery times (often 7–21+ days depending on shipping option), though some items may ship from regional warehouses faster.
  • Zalora: strong local presence in Singapore — faster delivery options, same-day/next-day for many items during promotions.

• Returns & customer service

  • Zalora: straightforward local returns/refunds, customer support in-region and faster resolution.
  • SHEIN: returns can be more complex and slower (often international returns or limited local return options); customer support responses can be slower.

• Payment & checkout

  • Both support cards and popular local payment options; Zalora often supports more local payment methods (PayNow, local wallets) and gift vouchers/cash on delivery promotions at times.

• Trust, authenticity & brand assurance

  • Zalora: more reliable for authentic brand items and branded merchandise.
  • SHEIN: mostly its own private-label items and marketplace sellers; not a place for guaranteed branded goods.

• Sustainability & ethical considerations

  • Both are fast-fashion heavy; Zalora carries some sustainable/ethical brands and better brand transparency for those options. SHEIN has improved communications but still gets criticism for throwaway fashion and manufacturing opacity.

Who should pick which

• Choose Zalora if you want: faster delivery, easier returns, reliable sizing/quality, and genuine brand-name items.
• Choose SHEIN if you want: lowest prices, the widest and newest trend selection, and are willing to accept variable quality and longer/complicated returns.

Practical tips

• On SHEIN: always check product reviews and buyer photos, measure against the item size chart, and expect to buy extras if you’re unsure of fit.
• On Zalora: look for promo codes, filter by brand for authenticity, and use their return window if unsure.
• For expensive or time-sensitive purchases, prefer Zalora (local support). For cheap trend items, SHEIN is fine if you accept the risks.

If you want, I can compare current delivery times, return windows, or active promo codes for both specifically in Singapore — tell me which detail you want and I’ll look them up.