How many participants do I need to recruit for user research?

In order to answer this question, you’ll need to ask yourself a few more: What kind of study are you doing? What is your budget? How much time do you have? All of these things play a part in how many participants you can and should recruit for your research. 

For qualitative studies, 5 to 10 participants is typically plenty. But for quantitative research, you’ll need at least 40 to have a representative sample. That’s according to Kate Moran, UX Specialist at Nielsen Norman Group:

“A lot of times we advise people that if you're doing qualitative [user testing], you can get away with anywhere from 5 to 10 participants. Because in a qualitative study, we want to find out what's wrong with this thing, what's not working, and we want to get ideas [to help us] fix it.

With a quantitative study, we’re trying to get a random sample that's going to represent an entire group of people. So we want to have some amount of accuracy there. For [quantitative user testing], we usually recommend having about 40 participants.”

👂 Listen to the full episode: UX Benchmarking to Demonstrate ROI with Kate Moran, UX Specialist at Nielsen Norman Group

📚 Related Reading: Participant Recruitment in Qualitative Research

For user interviews and usability testing—where the focus is on getting in-depth responses from representative participants—you can start with about 5 people and scale up until you start hearing the same things from many participants. Jon MacDonald, Founder of The Good, says:

“I get this question from brands quite a bit, which is, “How many user tests are you going to do if we work together?”, and the number is super low: we start with five. 

Anything over five initially is really not going to tell you anything. It's not going to be that eye opening. We would rather go deep with those five. And then if we start really finding some areas that need a lot more research, we'll start focusing in and run another batch of five on just one area.

If you find somebody who [fits] that ideal customer profile or ideal user, and you have done your homework, that is going to be way more valuable than just allowing anyone to [participate].”

👂 Listen to the full episode: Using User Research to Improve Conversion Rates with Jon MacDonald, Founder of The Good

Starting small can also benefit researchers conducting larger studies, like diary studies. It can help you validate how successfully you’re recruiting for your ideal profile, and can also help you troubleshoot your study to make sure your questions are clearly worded and easy to understand. Tony Turner, Lead UX Researcher at Progressive Insurance, advises:

“Do a dry run with a couple of participants, just to make sure that some of those responses are what you're looking for. That's really important for any kind of study, but it's super important for a diary study.

Because if it's something that's happening over [a long period of] time, you don't want to find out later that you had some problems with your questions.”

👂 Listen to the full episode: The Magic of Diary Studies with Tony Turner of Progressive

💡Did you know? 63% of user researchers say they start recruiting 1 week or more in advance. Check out the ✨The State of User Research 2021 Report✨ for more insights on UXR recruiting methods, tools, and timelines.

How much should I pay my user research participants? 

What’s an hour of research time really worth anyway? 

The purpose of research incentives is to provide something of value to your participants as a ‘thank you’ for their effort. Some customers may be enticed by cold, hard cash. However, some customers may see more value in alternative incentives, like private webinars or upgraded support. Teresa Torres, founder of Product Talk, recommends getting creative with what you offer:

“I worked with a company, Snag a Job, [which is] a job board for hourly workers. So they offered $20 for a 20 minute interview. When you went to their home page, an interstitial would pop up that said [something like] "Hey, do you have 20 minutes for us? We'll pay you $20." What's nice about that offer is 20 minutes is a small amount of time. And for an hourly worker who's likely making minimum wage, $20 for 20 minutes is a high value.

Enterprise companies can do this as well. If you're [a company like] Salesforce, and people work in your product all day every day, this type of recruiting will also work. But $20 probably isn't going to cut it. 

In fact, I think for enterprise clients, cash is rarely the right reward. You have to look at: what's something valuable that you can offer? And it could be anything from inviting them to an invite-only webinar [to] giving them a discount on their subscription for a month [to] giving them access to a premium helpline." 

👂 Listen to the full episode: How to Interview Customers Continuously with Teresa Torres of Product Talk

To dive deeper into this question, read our Ultimate Guide to User Research Incentives, which looks at data from over 25,000 sessions. We even created an incentive calculator—plug in a few facts about your study and get customized research incentive recommendations.

How do you recruit quality participants for user research?

One of the keys to recruiting good participants for research is to create a robust and effective screener survey. A screener is a survey participants take before they are accepted into your research study. The questions should focus on the qualities, behaviors, and habits a participant needs to have to qualify for your study and provide you with useful feedback. Tony Turner of Progressive Insurance suggests including open-ended questions in your screener that let you learn about "their previous experiences and how long they've been using certain applications."

“Focus on recruiting early. Have questions in the screener that give them an opportunity to be verbose, or not, [and learn] about them that way. [Learn] about their previous experiences and how long they've been using certain applications”

👂 Listen to the full episode: The Magic of Diary Studies with Tony Turner of Progressive

Many researchers also like to include at least one open-ended question to gauge how descriptive participants are. Will they be able to describe their thoughts to you in enough detail to make their feedback useful? You can get a sense of this by asking a simple question like “describe what you did this morning” or ask something about your study specifically. 

Where you recruit your participants also matters. If you only ask people who have completed a survey on your site what they think of you, you’ll likely get people who feel strongly one way or another. Kate Moran of Nielsen Norman Group explains that:

“You tend to see polarization. You either see people who are very happy with you or people who completely hate you. And a lot of times … that has to do with how you structure the survey, like when you have a really long survey that takes people a long time to complete. Then it's more likely that the only people who are going to sit there and go through all that are going to  be people who love you and want to tell you how great you are, or people who hate you and they're going to go through all that just so they can tell you about this one thing they're mad about." 

👂 Listen to the full episode: UX Benchmarking to Demonstrate ROI with Kate Moran, UX Specialist at Nielsen Norman Group

How much does it cost to recruit participants for user research?

Probably more than you think. When you take into account the time your team spends recruiting and vetting participants, going it alone can get pretty pricey. Don’t believe me? Check out our cost savings calculator, which can show you how much using a recruitment tool can save you. Leo Smith, Director of User Research at a large insurance company breaks it down:

“We crunched the numbers. We were looking at how long on average it was taking us to recruit for a study. And it was anywhere between 25 and 40 hours in total across multiple people, across different teams.

And then we looked at how long it took us with a recruiting service. [With] the recruiting service, there's still some time overhead. You still have to write the screener and I still do the double recruiting [as] I call it—you know, the followup message to make sure they are the right people before approving them.

But generally speaking, that was an 80% time savings. And that's what we presented to stakeholders. It was so clear, in terms of what this tool was going to cost us versus how many hours it was going to save. It was so blindly obvious that it was going to be a massive return on time invested.”

👂 Listen to the full episode: Optimizing Your User Research Tool Stack for ROI with Daniel Loewus-Deitch and Leo Smith

Should I build a panel of my own participants for user research? 

An internal panel of participants can be really helpful for teams who want to get research done ASAP. It’s easier to call on current customers who have a vested interest in making your product better through feedback than to go out and recruit new participants every time. Danielle Smith, Sr. Director of Experience Research & Accessibility at Express Scripts shares how her team finds specific participants, fast: 

“We have an internal recruiting panel. If we want to do some sort of special study where we need really specific participants, then the user research team can do that themselves because the data science team has already built out that panel for them.”

👂 Listen to the full episode: From Start to Finish: End-to-End Experience Teams with Danielle Smith of Express Scripts

Many teams use their own panels to conduct research on new features with experienced users. If you want to build your own panel, you can get started for free with Research Hub from User Interviews. With Research Hub you can reach out to your users, schedule research sessions, and even dole out incentives. 

How do I put these user research recruiting tips to good use? 

Now that you’ve heard from the UXR pros, it’s time to put all that research recruiting advice to work! We’ll even give you a gift to get you started—recruit three participants for your first project, free. 

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