How do I find out which third-party services a SaaS product pays for each month?

Start with the statements, not the seller’s memory. Mark every repeated charge and any annual payments that fall outside the monthly view. Ask the seller to label each: hosting, email delivery, payment processing, monitoring, analytics, support tools, licences, contractors. Anything unlabelled is a question for the next conversation.

Then ask which of these are critical. Some services can be swapped in an afternoon; others are woven into the product. Ask who holds each account and whether it is in the seller’s name, a personal email or the business’s. Accounts under a personal login must be moved before closing.

Ask a developer to look through the code for services called by the product that do not appear on the statements. Those might be free tiers that will become paid as use grows, or accounts someone else is paying. Also check the costs against the accounting records, and ask your accountant about anything that is missing. Finally, ask about price increases the seller expects. Ask for a one-page diagram of how the services connect, drawn by the person who built it. If nobody can draw it, you have learned something important about how well the product is documented.

Key takeaways

• List every recurring charge from the bank and card statements.
• Ask which services the product cannot run without.
• Have a developer check the code for services missing from the statements.