Stripe is the rare tool that is genuinely easy to start with. You can take a payment in an afternoon. That is exactly why it is so easy to get wrong: the demo is trivial, and the production version, the one that handles real money reliably, is not.
The mistakes below do not throw build errors. They show up weeks later as silent revenue leakage and a slow drip of support tickets.
1. Treating webhooks as optional
Your app should never decide that a subscription is active because the checkout page redirected back. The source of truth is the webhook. If you do not handle invoice.paid, customer.subscription.updated, and the rest idempotently, your billing state drifts from Stripe's, and you find out when a customer emails asking why they were charged for a plan they cancelled.
2. Ignoring proration
The moment you have more than one plan, customers upgrade and downgrade mid-cycle. If you are not handling proration deliberately, you are either overcharging or giving away revenue. Neither is a good look, and both erode trust.
3. No dunning for failed payments
Cards fail constantly. Expired cards, insufficient funds, fraud blocks. Without a retry and recovery flow, a failed payment just becomes silent churn. A proper dunning sequence recovers a meaningful share of that revenue automatically.
4. Underestimating marketplace payouts
If you are paying out to third parties, Stripe Connect is a different level of complexity: onboarding, KYC, split payments, and a whole second set of webhooks. Teams routinely scope this like a normal integration and then stall.
5. Leaving tax for "later"
Tax is not a feature you bolt on at the end. Where it applies, it shapes the checkout and invoice flow from the start. Retrofitting it is painful.
The fix is boring on purpose
None of this is exotic. It is idempotent webhook handling, tested edge cases, and admin visibility so billing state always matches product state. The hard part is discipline, not cleverness.
When we shipped Stripe end to end for a Western Europe startup, the first task was a Stripe-billed admin panel. Getting that right is what turned one task into a dedicated team.
If you want this handled by engineers who have shipped it in production, see how we approach Stripe integration, or start with a readiness audit.
Ihor Chalapchii