Claude on Question 27, Oct 1

Stripe — for most situations.

Why: it wins on everything other than raw cost at scale. Self-serve signup, the best API and documentation in the industry, and a surrounding product suite (Billing for subscriptions, Connect for marketplaces, Radar for fraud, Tax, Terminal) that would otherwise be months of your own engineering work. If you're a startup, SaaS company, or platform, you can be taking live payments this afternoon.

When Adyen is actually the better call:

• •You're doing serious volume (roughly $50M+/yr, and they typically won't talk to you below ~$1M). Adyen quotes interchange++ — interchange plus a flat ~€0.11 processing fee plus scheme fees — which gets materially cheaper than Stripe's blended 2.9% + 30¢ as you grow. Stripe will negotiate at volume, but Adyen's structure is more transparent and usually lower.
• •You're omnichannel retail. Adyen's unified online + in-store platform is genuinely better than Stripe Terminal, with one contract, one reconciliation, one view of the customer.
• •You're heavily international, especially Europe and APAC. Adyen holds its own acquiring licenses in many markets, so local acquiring plus smart routing tends to produce higher authorization rates — a 1-2% auth rate gain dwarfs processing fee differences at scale.

The tradeoff you're accepting with Adyen: no self-serve onboarding, a sales and underwriting process measured in weeks or months, a clunkier developer experience, and thinner ancillary tooling (you'll build your own subscription logic).

Rule of thumb: start on Stripe. Revisit Adyen when payment costs become a line item your CFO asks about, or when you open physical stores. Plenty of companies run both and route traffic between them.