Shopify Pay is a payment system built-in into Shopify. Stripe is a third-party solution provided by Stripe. While both systems can offer basic functionality like accepting various payment types or supporting multiple currencies, the availability and payment fees vary. For instance, Shopify Payments is available in 17 countries, while Stripe is in 44 countries.  Also, Shopify Payments doesn't charge any transaction fees, while Stripe charges 1.4% + 0.25€ for European cards and 2.9% + 0.25€ for non-European cards per transaction.  On top of Stripe's fees, Shopify adds extra fees for third-party gateways (like Stripe): 2% for Basic Shopify, 1% for Shopify, and 0.5% for Shopify Advanced plans. There are other differences between the systems, like in fraud detection, chargebacks, too.