Customer Interview Guide Template

For most product questions, 8-12 interviews reach saturation (you start hearing the same patterns). For narrow, well-defined questions (e.g., "Why did 3 customers churn last month?"), 5-6 may suffice. For broad exploration of a new market, 15-20 may be needed. Stop interviewing when the last 2-3 interviews add no new patterns. The [Product Discovery Handbook](/discovery-guide) covers sample size planning in detail.

For B2B customer interviews, avoid cash incentives. They attract people motivated by the payment rather than genuine experience. Instead, offer value: share research findings, provide early access to features, or simply respect their time by keeping the conversation to 30 minutes. For prospect interviews (people who have no relationship with you), a small gift card ($25-50) is acceptable.

Three rules: (1) Ask about past behavior, not hypothetical future. "Tell me about the last time..." not "Would you use...?" (2) Ask open-ended questions. "How do you handle X?" not "Do you find X difficult?" (3) Never describe a feature and ask if they want it. Instead, describe the problem and ask how they deal with it today. Use the [Jobs to Be Done Framework](/frameworks/jobs-to-be-done) to structure questions around outcomes.

Take them seriously. If 8 out of 12 interview participants describe a problem your roadmap does not address, that is a signal worth investigating further. Present the findings to your team with the evidence. Use the [RICE Calculator](/tools/rice-calculator) to compare the newly identified opportunity against existing roadmap items. Insights that contradict your assumptions are the most valuable kind.

Three approaches: (1) Ask your CS or sales contact to make the introduction. (2) Frame the ask as "I want your perspective on [industry trend]" not "I want to ask about our product." (3) Keep it to 20 minutes and respect the time strictly. Executives are more willing to share strategic insights when you ask about their business challenges rather than your product's UX. ---