How to Deal with a Know-it-all at Work

We've all known at least one know-it-all in our lives—and if you're here, you’ve likely run into one at work. Maybe it's that coworker who always has to interject with “actually…” or the person who seems convinced that their perspective is the only right one. These aren’t just people who think they know everything; their approach can feel dismissive, even condescending—especially if they’re also prone to mansplaining.

Are you facing a person who knows a lot about everything—and isn’t shy about showing it? How do you deal with a know-it-all? Let us walk you through it.

What’s a know-it-all? Examples    

A know-it-all is someone who feels compelled to display their knowledge (or supposed expertise) at every opportunity, often dismissing others’ ideas in the process.

While the know-it-all meaning is generally understood, highlighting specific comments and reactions can help clarify the behavior. These unsettling sayings often reveal their need to dominate conversations or dismiss other viewpoints, painting a clearer picture of the know-it-all's tactics:

• Actually, that’s not how it works.

• Well, I don’t think that approach makes sense, and here’s why…

• I’m just trying to help you understand the right way to do it.

• I know more about this than most people.

These types of remarks tend to shut down discussion, as they often imply that only their perspective is valid. Being able to recognize these patterns can help you prepare for interactions and respond with confidence.

The challenges of working with a know-it-all

Working alongside a know-it-all coworker can stifle creativity, dismiss valuable contributions from others, and create an uncomfortable work environment. 

“It’s one of the most frustrating experiences because they stifle the opportunity for others to voice their opinions and drive the growth of ideas,” says career coach Melissa Trager.

“It often comes across as dismissive,” says Jessi Gholami, a licensed therapist. “I’ve worked with a fair number of these types, and it’s hard to get through those interactions without feeling overlooked or, quite frankly, rather irritated!”

A coworker know-it-all can be driven by insecurity rather than expertise. And while the behavior may come off as arrogant, it often has little to do with actual knowledge or skill.

For women in particular, dealing with a Mr. Know-it-all who tends to mansplain can be especially draining. Handling such dynamics requires both patience and skill to ensure your own ideas are heard without escalating tension or unnecessary conflict.

How to handle a know-it-all coworker

While it may be tempting to simply avoid a know-it-all coworker, doing so isn’t always realistic or beneficial in a professional setting. If left unchecked, this behavior can create a lopsided environment where only one person’s perspective is acknowledged, limiting team growth and collaboration. 

By addressing the issue, you can help foster a healthier team dynamic, maintain your own boundaries, and create space for a more balanced exchange of ideas. 

So, how to deal with a know-it-all at work? Let’s explore some strategies.

1. Stay calm and stick to the facts

A know-it-all may try to engage in back-and-forth debates that can feel exhausting. Stay calm, and keep your responses short and fact-based. “What works for me is staying calm, sticking to my own perspective, and letting their comments roll off,” Gholami says.

“A quick ‘I’ll keep that in mind’ or just a straightforward reply usually keeps things respectful without inviting a back-and-forth,” she says. If you’re feeling especially drained, try to ground yourself by focusing on the task at hand rather than engaging in an ego-driven conversation. Short, direct responses like “Thanks for your input” can go a long way.

2. Ask questions to redirect the conversation

Sometimes, rather than disagreeing outright, asking questions can help steer the conversation in a more collaborative direction. 

“Early in my career, one team member would dominate the conversation, repeatedly insisting they were the most knowledgeable,” says entrepreneur Taylor Moore. “It was initially undermining, mainly because his input was never as accurate as he made it seem.” 

Instead of letting frustration drive me, I changed tactics,” Moore says. “I specifically asked him questions directly and pointed out areas where other people’s insights were essential. Just a little redirection made him feel valuable and created a better dialogue.”

By showing genuine curiosity and involving others in the discussion, you subtly assert your own perspective while encouraging collaboration.

3. Set boundaries and prioritize your mental health

For your own well-being, limit unnecessary interactions with a know-it-all coworker. “These types are extremely frustrating, and it’s not worth the energy to surround yourself with someone who isn’t open to hearing your ideas,” Trager says.

If you must engage with them regularly, make sure to set clear boundaries. Politely acknowledge their input, then proceed with your work without lingering on their opinions. This can help maintain your focus and reduce the impact of their behavior on your mood and productivity.

4. Use “I” statements to assert yourself

Assertiveness is your friend in these situations. Use “I” statements to keep the focus on your own experience, rather than triggering a defensive response. Phrases like, “I think we could try another approach” or “I’d like to explore other perspectives on this” can subtly signal that you don’t view their opinion as the final word.

For women dealing with Mr. Know-it-all at the workplace, a respectful but firm approach is key. “Confidence and clarity are essential; balancing assertiveness with empathy is what it’s about,” Moore says. “For example, I used phrases like, ‘That’s an interesting approach.’ Then I added, ‘From another angle, we could ponder….’”

5. Find support among colleagues

Workplace dynamics are often easier to handle with the support of trusted coworkers. Seek out allies within your team who respect open communication and support diverse perspectives. Whether you can turn to them for a quick chat about strategies for handling difficult personalities or to simply vent about the day, having a support system can be a relief.

What to avoid when dealing with a know-it-all coworker

While tackling this challenge, there are a few pitfalls to watch out for.

• Getting into an argument. Engaging in a back-and-forth with a know-it-all can be tempting, but it’s rarely productive. Instead, stick to calm, neutral responses.

• Taking it personally. A Mr. Know-it-all (or a Ms. Know-it-all) often behaves this way with everyone. Remember, their need to dominate is more about their insecurity than anything else.

• Letting it impact your confidence. It’s easy to feel diminished by constant interjections or interruptions. Don’t let this behavior undermine your self-assurance. Stay centered on your own strengths and expertise.

Maintain composure—and confidence

Dealing with a know-it-all at work isn’t easy, but by using these strategies, you can help create a more balanced and constructive environment. Whether it’s calmly asserting your ideas, asking clarifying questions, or finding allies within your team, handling these interactions thoughtfully can protect your peace and help preserve a healthy work culture.

Know-it-alls can be frustrating, but they don’t have to derail your workday or your confidence. With patience, clear boundaries, and the right strategies, you can navigate these challenging personalities—and maybe even find ways to turn their know-it-all energy into something constructive for the team.