How Do I Interview Customers to Test a Business Idea?

By Bill Stilwell · Last reviewed October 16, 2026

The short answer

Talk to 10 to 20 people who have the problem you want to solve, and ask about what they’ve already done, not what they might do someday. Cover five things: the problem, how urgent it is, what they use now, how they buy, and what they’ve paid. Write down their exact words, because those words become your service names, website copy, and the phrases people type into Google.

What this means

A customer interview is a short, one-on-one talk with someone who has the problem your business would solve. You’re not selling. You’re learning.

The outline lists five topics to cover:

Problems: what goes wrong for them, in their words
Urgency: how fast they need it fixed (see 7.3.2 Problem Frequency and Urgency)
Current alternatives: what they do about it now (see 7.3.4 Current Alternatives)
Buying behavior: how they found and chose help last time (see 7.3.6 Buying Triggers and 7.3.8 Search Behavior)
Willingness to pay: what they’ve paid before, and what felt fair (see 7.4.6 Price Expectations)

Example: someone wants to start a gutter cleaning business. Instead of asking “Would you hire a gutter cleaner?”, they ask homeowners, “When did you last clean your gutters? Who did it? How did you find them? What did it cost? What annoyed you?” Several people say they couldn’t get anyone to call back. That tells the owner fast response may matter as much as price.

Why it matters

Friends and family are too kind. They’ll say it’s a great idea. Strangers who have the problem give you facts.
Guessing costs money. Building a website, buying a truck, or signing a lease for an idea nobody needs is expensive.
You learn the words that sell. Customers describe problems differently than owners do. Their words work better on your website and profile.
You find the real objection. Price is often not the main worry. Trust, timing, or hassle may be.

Who this applies to

Everyone starting a business, and anyone adding a new service or product. Even if you’ve worked in the trade for years, interviews show you how customers see it.

How to do it

Write down who you want to talk to (see 7.1.4 Ideal Customer).
Find 10 to 20 of them. Try neighbors, local groups, past coworkers’ customers, or people who posted about the problem online. Avoid close friends and family when you can.
Ask for 15 to 20 minutes. Say you’re researching, not selling.
Use open questions about the past. Good ones:

“Tell me about the last time this happened.”
“What did you do about it?”
“How did you find who you hired?”
“What did it cost, and how did that feel?”
“What would have made it easier?”

Avoid questions about the future, like “Would you buy this?” People often say yes and then don’t.
Write down their exact phrases, not your summary.
Never pitch during the interview. If they ask, tell them at the end.
After each interview, fill in a simple table: problem, urgency, current fix, how they found help, what they paid, and key phrases.
Look for patterns after 10 talks. If you hear something new every time, keep going.
Use what you learned in 7.9 Proceed, Revise, or Stop Decision.

What proof to keep

Your list of questions and the date you used them
Notes from each interview, with names removed or coded
Your summary table of answers
A short list of exact customer phrases

Store these in your business planning folder. Ask permission before recording anyone, and don’t keep personal details you don’t need (see 11.6.1 Data Minimization).

Common mistakes

Asking “Would you buy this?” It gets polite yeses. Ask what they did last time.
Pitching instead of listening. Once you sell, they stop telling the truth.
Only talking to friends. They want to be supportive.
Stopping at 3 interviews. You can’t see patterns that early.
Writing your own summary instead of their words. You lose the language that matters most for your website and profile.
Ignoring answers you don’t like. The point is to find out if you’re wrong before it costs money.

When to get help from a pro

Most owners can do this alone. Your local Small Business Development Center or SCORE mentor can review your questions and help you read the results. Ask:

Are my questions leading people toward the answer I want?
What patterns do you see in my notes?

Bill’s note

[Bill: add a short story or opinion here. For example, a phrase a SiteSmarty prospect used that you now use on your website, or an interview that changed what you offer.]

How I did this for SiteSmarty

[Date I did this:]
[What I actually did, step by step: who I interviewed, how many, and how I found them]
[What it cost and how long it took:]
[What surprised me or what I’d do differently:]
[Screenshot or photo to add, with private info blurred: my interview notes sheet and summary table]
[Result so far:]

Questions people ask

How many customer interviews should I do? Start with 10 to 20. Stop when you keep hearing the same answers.

What questions should I ask? Ask about the past: the last time they had the problem, what they did, how they found help, and what they paid.

How do I find people to interview? Local groups, neighbors, online forums where people talk about the problem, and people in your target customer group you don’t know well.

How do I avoid polite answers? Don’t pitch, don’t ask about the future, and don’t interview close friends if you can avoid it.

Audit check

Question: Did the owner interview at least 10 people who have the problem, using questions about past behavior, and record their exact words?
Pass looks like: 10 or more interviews with real prospects. Questions about past actions. Notes with exact phrases. A summary table showing patterns.
Fail looks like: Only friends and family. Questions like “Would you buy this?” No notes. A pitch disguised as research.
Evidence to collect: Question list, interview notes, summary table, and phrase list.

Where this fits

Do this first: 7.1.3 Customer Problem, 7.1.4 Ideal Customer

Do this next: 7.3.2 Problem Frequency and Urgency

Sources

U.S. Small Business Administration, "Market research and competitive analysis" (checked October 16, 2026)
Google Business Profile Help, "Tips to improve your local ranking on Google" (checked October 16, 2026)

This page explains general rules and Bill's own experience. It is not legal, tax, or insurance advice. Talk to a qualified professional about your situation.