Costco's North American websites (costco.ca and costco.com) don't use the term VAT because Canada and the US don't have value-added tax systems. In Canada, you see prices before tax on product pages, then GST, HST, or PST gets added at checkout depending on your shipping province. Ontario shoppers pay 13% HST, Alberta pays 5% GST, and so on. The US site works the same way with state sales taxes applied at final checkout. In markets where Costco operates under VAT regimes—like the UK (costco.co.uk), Spain, France, or Japan—the website must comply with local consumer protection laws. EU regulations require B2C e-commerce sites to display VAT-inclusive prices prominently, so Costco UK shows prices with the 20% VAT already included. Business members can often see VAT-exclusive pricing after logging in with a trade account. From a web design perspective, this creates interesting localization challenges. Costco runs separate regional platforms rather than one global site, which means each market's tax display logic is hardcoded into that region's checkout flow. A Canadian developer working on costco.ca doesn't need to handle VAT calculations at all—the system only needs to map postal codes to the correct GST/HST/PST rates. At Ottawa SEO, when we build e-commerce sites for clients shipping internationally, we typically integrate tax plugins that detect user location and apply the correct regime. Shopify and WooCommerce both handle this automatically for Canadian GST/HST, but adding EU VAT compliance requires extensions like WooCommerce EU VAT or Quaderno. The key decision is whether to show tax-inclusive or tax-exclusive prices by default, which depends entirely on your primary market's legal requirements and customer expectations. Costco's approach—separate regional sites with localized tax treatment—works at their scale but most smaller operations use geo-detection on a single platform.