3 Margin Mistakes Every E-commerce Founder Makes

You launched a product. It's selling. But are you actually making money? Here are the three mistakes that turn profitable-looking products into money losers.

Mistake 1: Forgetting Platform Fees

Amazon takes 15%. Shopify payment processing is ~2.9%. Then there's FBA fees, storage fees, and advertising costs. If you priced your product at 2x COGS, you're probably losing money.

Mistake 2: Ignoring Inflation

Your supplier raised prices 8% last quarter. Did you update your prices? If not, your margin just got eaten alive.

Mistake 3: Not Accounting for Returns

A 5–10% return rate is normal for e-commerce. If you didn't build that into your pricing, every return comes directly out of your margin.

The Fix

Use a pricing calculator that includes ALL costs: COGS, platform fees, shipping, returns, taxes, and your target margin. FlowCFO's e-commerce agent does this automatically and alerts you when cost increases erode your margin below your threshold.