Informal interviews are qualitative conversations that follow the participant's lead rather than a rigid question list. They are used in ethnographic research, exploratory market research, expert discovery, and any context where the researcher needs to understand how someone thinks about a topic without constraining that thinking with pre-set categories. Done well, they produce data that structured interviews cannot: unexpected angles, candid admissions, and the language participants use when they are not performing for an interviewer.
Done poorly, they produce pleasant conversations with little analytical value.
What makes an interview informal?
The distinction between formal and informal interviews is not about politeness. It is about structure. A formal or semi-structured interview follows a predetermined guide: the same topics are covered in roughly the same order for every participant. An informal interview follows the participant: the researcher has a set of interests or questions they want to explore, but the conversation evolves based on what the participant says rather than what the guide prescribes.
Informal interviews are most useful in three contexts:
Exploratory research where the researcher does not yet know what questions to ask. If you are entering a new market, domain, or organisation for the first time, a rigid question guide assumes you understand the landscape well enough to know what matters. An informal conversation with someone who lives in that landscape reveals the map before you commit to a route.
Building on formal data when structured interviews have surfaced a pattern the researcher wants to understand more deeply. An informal follow-up conversation about a specific finding is often more productive than scheduling another formal interview.
Naturalistic settings where formal research dynamics would change the phenomenon being studied. A retailer trying to understand how customers actually experience a store, or an ethnographer living within a community, uses informal conversations that fit into the natural flow of activity rather than extracting participants to a formal interview room.
Building rapport before you get to the substance
The quality of an informal interview depends almost entirely on how comfortable the participant feels speaking candidly. Rapport is the precondition. Without it, the participant stays at the surface: polished, socially acceptable answers that tell you what they want you to think rather than what they actually experience.
Rapport is built faster than most researchers expect, but it requires deliberate choices:
Match the register of the conversation. An informal interview that opens with "So for the purposes of this research, I'd like to explore your experience of..." is already pulling away from informality. Start conversationally: "How long have you been working in this area?" or "I read a bit about your background before we spoke: how did you get into this?"
Show real curiosity before asking about the topic you care about. Ask about something adjacent to your real interest first. If you are researching how procurement managers evaluate software vendors, ask them about their career path into procurement before you ask about software evaluation. This establishes that you are interested in them, not just their opinions on your research question.
Use their language, not yours. If a participant uses a term or phrase that is specific to their context, reflect it back to them in your probes. This signals that you are listening, and it prevents the conversation from defaulting to the researcher's framing.
Normalise not knowing. In an informal interview, "I'm not sure if I'm asking this clearly" or "I don't fully understand that. Can you help me understand what you mean?" signals openness rather than inadequacy. Participants in informal settings respond well to the researcher asking questions because they actually want to know, not because they are performing the role of interviewer.
Questions that work in informal settings
Invitation questions
These open the conversation and establish that the researcher wants narrative, not facts.
- "Tell me how you got to where you are."
- "I'd love to understand how [topic area] actually works from your perspective."
- "Walk me through what a typical [day/situation/decision] looks like for you."
- "Before we get into specifics, can you give me the lay of the land as you see it?"
The key characteristic is that they invite the participant to begin wherever they want. In a formal interview, the researcher controls the starting point. In an informal interview, where the participant begins is itself data.
Curious follow-on questions
These respond to what the participant has said rather than moving to the next item on a list.
- "You mentioned [phrase they used] — I hadn't thought about it that way. What do you mean?"
- "That's interesting. What happened next?"
- "Is that typical, or was that a one-off?"
- "Why do you think that happens?"
- "Can you give me an example of when that played out?"
These questions signal that you are listening and that you want to go deeper, without leading the participant toward a specific answer. The most productive informal interviews are driven almost entirely by curious follow-on questions rather than a prepared list.
Devil's advocate questions
In informal settings, researchers can test ideas and invite disagreement in ways that formal interview settings make awkward.
- "I've heard some people say [opposing view]. How does that fit with what you're describing?"
- "Is there a scenario where that doesn't hold?"
- "What would someone who disagreed with you say?"
- "Where do you think you might be wrong about that?"
Participants in relaxed, conversational settings are often surprisingly willing to engage with these questions seriously. They can surface the complexity and uncertainty that more polished formal responses smooth over.
The "what I really wanted to ask" question
Saved for the end of an informal conversation, this question often produces the most valuable data.
- "Is there something I should have asked that I didn't?"
- "What's the thing people don't usually talk about when they discuss [topic]?"
- "If you were explaining this to someone who had no idea about it, what would you make sure they understood?"
These questions invite the participant to shape the research agenda. What they choose to raise is often what has been at the back of their mind throughout the conversation.
Getting beyond the obvious
The "obvious" in an interview is whatever the participant expects you want to hear, or whatever they have said many times before. Both produce thin data.
Get specific as quickly as possible. General claims ("the culture here is very collaborative") rarely produce insight. Specific instances ("can you think of a time when that collaboration actually made a difference to an outcome?") reveal what the claim actually means and whether it is accurate. The move from general to specific is the most reliable route past the obvious.
Welcome silence. Most interviewers fill silences too quickly. A pause after a participant finishes speaking often produces the next, less-rehearsed thought that follows the polished initial response. Count to three before asking the next question. This is harder than it sounds and worth practising.
Follow the hesitations. If a participant pauses before answering, hedges with "well, it's complicated" or "it depends," or qualifies a statement with "mostly," those are signals that there is more complexity than the surface answer suggests. "You hesitated there. What's the complicated part?" is often the most valuable probe available.
Ask about the exceptions. The typical-case description is the obvious answer. The exception case reveals the underlying mechanism. "When does that not work?" or "Is there a situation where you would do it differently?" consistently surface more insight than asking about the normal case.
Invite the embarrassing or uncomfortable. This requires a degree of trust and tact, but informal settings can support it. "I imagine that's a difficult conversation to have" or "It sounds like that creates some tension" gives the participant permission to acknowledge difficulties that a more formal research context would have them skip over.
Moving from informal conversation to analysable data
Informal interviews produce messy, non-linear data. Participants jump around, change their minds, use inconsistent terminology, and blend factual claims with interpretive ones. The analytical challenge is to preserve that richness while building a structure that allows comparison across multiple conversations.
Record and transcribe. Memory-based notes from informal conversations are unreliable for analytical purposes. Recording (with consent) and full transcription is the baseline. AI transcription tools have made this practical for most research settings. See the practical setup for audio interviews for the workflow.
Code for themes, not answers. Unlike formal interviews where you can code responses to each question systematically, informal interviews are coded thematically. You identify what themes appear across conversations and where each participant's discussion of that theme sits in the transcript. Skimle's AI-assisted analysis handles this well: it processes multiple informal interview transcripts and identifies themes across the corpus, with full traceability from every theme back to the specific quotes that support it.
Note what is not said as well as what is. In informal interviews, what participants choose to omit (topics they avoid, questions they deflect, aspects of a situation they do not raise) is analytically significant. Keep a separate log of notable absences alongside the coded content.
Track rapport quality. In a formal interview, the instrument is relatively constant across participants. In informal interviews, the quality of the conversation varies. Note in your analytical memo which conversations produced deeper, more candid data, and treat high-rapport conversations as richer evidence than ones where the participant stayed guarded.
For the full analytical workflow, see how to analyse customer interviews and thematic analysis: a complete guide.
Informal interviews in different research contexts
Exploratory market research. Conversations with potential customers before a formal research programme begins. The goal is to understand how people frame the problem space before designing the questions. These conversations directly inform the guide for subsequent customer discovery interviews.
Expert network calls. Often run informally by consultants and investment researchers. The most valuable expert calls are conversational rather than interrogatory. See qualitative research for consultants for the application in a professional services context.
Ethnographic field research. Conversations that happen naturally during participant observation. The ethnographer participates in the setting and asks questions that arise organically from what is happening. For academic applications, see qualitative research examples for illustrative studies.
Internal research. Conversations with colleagues, customers, or stakeholders that are not formally designated as research but serve a research purpose. The informality of these conversations is both their strength (candour) and their analytical weakness (inconsistency). Treating them as data (by recording, transcribing, and coding them systematically) recovers the value that informal conversations typically lose.
Frequently asked questions
When should I use informal interviews rather than semi-structured ones?
When you are exploring unknown territory (you do not yet know what questions to ask), when the relationship with the participant calls for a conversational register, or when a formal research dynamic would distort what the participant says. Informal interviews work best early in a research process, as a source of hypotheses for formal investigation. They are less suited to research that requires direct comparison across many participants, because the lack of structural consistency makes comparison harder.
How do I record a conversation without it feeling awkward?
Transparency about the recording normalises it. Before the conversation starts, explain clearly that you will be recording for your own notes, that nothing will be shared without their review, and ask for consent. Most participants forget about the recording within the first few minutes. If recording would change the dynamic in a meaningful way (a particularly sensitive context), take structured notes immediately after the conversation, within the hour while memory is fresh, rather than relying on a recording.
How many informal interviews do you need before running formal ones?
There is no fixed number, but the signal to move to formal interviews is saturation of the unexpected: when informal conversations stop producing new angles or concepts you had not anticipated, you have likely captured enough to design a formal guide. For a bounded topic with a relatively homogeneous participant group, 5-10 informal conversations are often enough. For a complex or diverse topic, 15-20 may be needed.
Can informal interview data be analysed systematically?
Yes, with some additional analytical investment. The lack of a consistent guide means you cannot compare responses to the same question across participants, but you can compare themes. Systematic coding of informal interview transcripts, treating the full conversation as the unit of analysis rather than individual question responses, produces comparable and credible analytical output. AI-assisted coding tools like Skimle are particularly well suited to this, because they identify thematic patterns across a corpus of varied transcripts without requiring a fixed structure to code against.
Want to turn informal research conversations into systematic insights? Try Skimle for free and see how AI-assisted analysis finds the patterns across your interview corpus, even when the conversations followed very different paths.
Related reading: Good interview questions to ask: how to get the most out of any interview | How to conduct effective business interviews | Customer discovery interviews: a practical guide
About the authors
Henri Schildt is a Professor of Strategy at Aalto University School of Business and co-founder of Skimle. He has published over a dozen peer-reviewed articles using qualitative methods, including work in Academy of Management Journal, Organisation Science, and Strategic Management Journal. His research focuses on organisational strategy, innovation, and qualitative methodology. Google Scholar profile
Olli Salo is a former Partner at McKinsey & Company where he spent 18 years helping clients understand the markets and themselves, develop winning strategies and improve their operating models. He has done over 1000 client interviews and published over 10 articles on McKinsey.com and beyond. LinkedIn profile
