The psychology behind word-of-mouth marketing: Why we share, trust, and buy
By Andrew Littlefield●8 min. read●Jun 26, 2025
While many marketers are pacing around their home offices trying to stay ahead of the AI hype cycle, the savviest ones are doubling down on an old classic: word-of-mouth marketing.
It makes sense. In a low-trust digital environment, word-of-mouth is more valuable than ever. When you can’t tell if that influencer review is real or AI-generated, the most credible recommendation might come from your neighbor, your coworker, or a friend.
The numbers back it up. 92% of people trust word-of-mouth referrals more than any other form of advertising. Your customers are practically shouting from the rooftops: forget the shiny new tools for a minute and focus on what works.
But that’s the challenge, isn’t it? AI is automated. Word-of-mouth is messy. How do you build a repeatable, scalable strategy for a marketing approach that’s meant to feel organic?
Read on to explore the psychology of word-of-mouth marketing in 2025 and learn how to turn it into a systematic program that drives business results.
What counts as word-of-mouth marketing in 2025?
Word-of-mouth (WOM) marketing covers a wide spectrum of marketing channels in 2025. It might be a glowing recommendation from a neighbor, a passing comment in a group chat, or a rave review from a niche influencer your audience trusts more than the brand itself.
It’s hard to beat a referral from someone you know. 88% of people say they trust recommendations from friends, family, or colleagues more than any other channel. Local service businesses — think plumbers, contractors, landscapers — live and die by this. They don’t pour money into billboards; they earn trust, then let their customers spread the word.
Then there’s electronic word-of-mouth—social media posts, Reddit threads, online reviews. It’s messy, unstructured, and massively influential. Despite the sheer volume of influencer content flooding feeds, it still works. A 2024 Sprout Social study found that nearly half of consumers make daily, weekly, or monthly purchases based on influencer posts.
And now, AI is pulling word-of-mouth into new territory. ChatGPT and Google’s AI-generated results often surface Reddit threads, reviews, or forum posts, effectively treating anonymous stranger opinions as credible sources. It’s word-of-mouth with zero attribution, and yet it shapes buying behavior every day.
At this point, word-of-mouth includes nearly any message about your brand that doesn’t come from your brand. And in a climate of consumer skepticism, that makes it one of the most powerful tools in your marketing toolkit.
The science of sharing: 6 psychological triggers
Why do people share referrals? The reasons are varied, but the research shows some guiding principles that may surprise you.
Social currency and self-enhancement
People often share product experiences not just to inform, but to impress. Researchers Andrea C. Wojnicki and David Godes theorize that word-of-mouth is often driven by the desire to look like an expert.
For example, someone who considers themselves a skilled cook may be more willing to share a positive experience with their fancy new chef’s knife or a new farmer’s market because doing so signals to their friends that they know their way around the kitchen.
Triggers and top-of-mind cues
If you want people to talk about your brand, be interesting. If you can’t be interesting, be visible.
A 2011 Journal of Marketing Research study found that three things drive word-of-mouth:
Interest: Is it cool, surprising, or worth talking about?
Cues: Are there things in the environment that remind people of it?
Public visibility: Can people see others using it?
Outside of writing articles, I do a lot of videography work. Without fail, anytime I’m shooting with my Sony A7C, someone asks about it. It’s sleek. It sparks curiosity. And it positions me as an expert. That combination makes it a word-of-mouth machine.
Cues matter too. In that same study, researchers found that branded swag like hats or stickers generated more conversation than discounts or rebates. So if you’ve ever questioned the ROI of your brand swag, take heart: giveaways give consumers something to talk about.
Emotion and arousal (dopamine memory)
Things that stir strong emotions, whether positive or negative, are more likely to be shared. But not all emotions spark the same urge to tell others.
In a 2011 study, marketing researchers Jonah Berger and Katherine L. Milkman found that high-arousal emotions drive viral sharing. That includes awe (positive high-arousal emotion) and anger (negative), which both energize people to act. Sadness, by contrast, is intense but low-arousal — it tends to quiet people down rather than push them to share.
Additionally, neurobiologist James McGaugh researched how emotional reactions get etched into our memories. The hormones that regulate our brains are closely tied to the parts of our brains that create memories.
That’s part of why experiences are such rich soil for word-of-mouth marketing. The Broadway superfan who flies to New York and finally sees their favorite musical doesn’t just experience a great show: they create a memory worth sharing. And chances are, they will.
Public visibility and mimicry
“Keeping up with the Joneses” isn’t just an adage — it’s marketing science.
Data consistently shows that the more people adopt a product, trend, or idea, the more likely it is to spread. Social proof plays a powerful role in driving behavior. In one 2012 study, researchers examined how solar panels caught on in residential neighborhoods. When one homeowner installed panels, their neighbors were significantly more likely to follow suit.
Visibility inspires imitation. When people see others making a choice, they’re more inclined to believe it’s the right one.
Practical value and utility
People are often more likely to share something when it offers practical value for others. The sharing method changes based on the size of the audience.
Researchers have found that when broadcasting (sharing with a large audience) a piece of content, the person sharing is often most interested in appearing smart or savvy. However, when narrowcasting (sharing with an individual or small group), those motivations shift off of the self and onto helping others. When narrowcasting, they often share what is most useful for the person they’re sharing with.
This is where things like group chats (often referred to as dark social media due to the difficulty of tracking this traffic) come into play. People may share a shoe recommendation in their running club group chat, but they may not post about it on Instagram.
Stories as cognitive carrier waves
Humans are natural storytellers, not factoid machines. When consumers share information, they don’t just rattle off facts — they tell stories. Stories have a beginning, middle, and end, and they’re how people make sense of the world.
Research backs this up: not only do we communicate through stories, but hearing something in narrative form actually makes it easier to remember. Stories stick.
Take my camera, for example. I couldn’t recite the specs off the top of my head, but I do remember the story of why I bought it. I was doing real estate photography and video tours, lugging around two different cameras: one for photos, one for video. Eventually, I got tired of the hassle and traded them both in for a Sony that could shoot both. It doesn’t capture video quite as well as my old rig, and it doesn’t take photos quite as well as my old photo setup, but it does both well enough to justify only carrying one camera.
That’s the power of a good story: beginning (I used to carry two cameras), middle (I needed one that could do both), and end (now I do everything with one). That’s what we remember — and what we pass along to others.
Intrinsic vs. extrinsic motivation: When incentives help vs. backfire
Not all word-of-mouth marketing is created equal, and not all of it should be incentivized.
The self-determination theory states that people are most motivated when their actions feel self-driven, not forced or transactional. Consumers are wired to do things because they feel meaningful, enjoyable, or aligned with who they are. It’s also why incentivizing word-of-mouth can backfire. You want people to share a positive experience, not game the system for a $10 reward.
How do you strike the right balance? A smart strategy pairs intrinsic motivation (surprise, delight, and personal pride) with extrinsic motivation (rewards, discounts, and giveaways). That means creating moments people want to talk about, then giving them just enough incentive to take action.
Think of it as a two-part system:
Talk triggers create the spark. These moments of unexpected delight make someone say, “I’ve got to tell someone about this.”
Referral rewards fan the flames. By layering on an incentive, you provide an extra nudge so customers follow through and spread the word.
The key is to lead with meaning and let the reward follow. Make people feel something worth sharing, then give them a little extra reason to hit send.
Designing talk triggers: A 4-step playbook
You can’t compel WOM marketing, but you can engineer moments that catalyze it. Enter the talk trigger: a specific, intentional detail in the customer experience that gets people talking.
Great talk triggers aren’t random acts of delight. They’re strategic, scalable, and tightly aligned with your brand to drive referrals. Here’s a four-step playbook to build them:
1. Audit your experience
Start by mapping out your customer journey. Where are the highs, lows, and memorable moments? Look for the gaps where a small but meaningful change could flip the script. This is about finding opportunities, not fixing problems.
2. Craft your triggers
A good talk trigger hits three traits:
Unexpected: It breaks a pattern, in a good way.
Repeatable: It’s baked into the experience, not just a one-off stunt.
Relevant: It connects to your brand promise or customer values.
For example, on a recent Delta flight, I found a small handwritten card from the captain thanking me for my loyalty. It was unexpected, repeatable, and relevant to Delta’s premium brand.
3. Operationalize delivery
A talk trigger only works if it shows up consistently. That means aligning your customer support, product, and marketing teams to ensure the moment is delivered reliably.
4. Amplify with owned and earned channels
Once people start talking, fuel the fire. Encourage user-generated content. Highlight customer posts through your newsletter and social accounts. Give people reasons to share, and then amplify their reach with your brand’s audiences.
Measurement that moves budgets
Word-of-mouth is messy to track, but it’s not unmeasurable. Here’s a simple set of metrics to help your marketing team quantify it:
Net Promoter Score (NPS): “How likely are you to recommend us?” is a decent proxy for potential word-of-mouth.
Advocacy Index: Track how often customers actually refer others, via referral codes, testimonial opt-ins, or reviews.
Earned Media Value (EMV): Estimate the dollar value of organic buzz—customer videos, influencer mentions, press hits. What would it cost to get that same reach through paid media?
Word-of-mouth is often hard to find in standard analytics tools. Here’s how to make it more trackable:
Referral links and codes: Add unique links or promo codes to partner, employee, or customer referral programs to provide additional attribution.
Dark social tagging: Use “how did you hear about us?” surveys, social listening tools, and UTM parameters to capture shares happening in DMs, texts, or WhatsApp.
Offline WOM lift: Run geotargeted tests. Launch a referral campaign in one market, then compare lift against a control group. It’s not perfect, but it can give you directional data on the value of your WOM programs.
Common pitfalls and ethical considerations
Word-of-mouth works because consumers view it as genuine. Ethical missteps can tank the impact of WOM programs fast.
If someone is being paid, rewarded, or incentivized to recommend a product, that relationship must be disclosed. It’s not just a best practice, it’s federal law.
The WOMMA Code of Ethics, updated in partnership with marketers and the public, provides guardrails for ethical marketing practices. At its core, the code emphasizes three things:
Honesty of relationship: If someone is part of a brand program, they must clearly say so when promoting a product or service.
Honesty of opinion: Your brand can’t tell people what to say, and you shouldn’t try. WOM recommendations should be real.
Honesty of identity: No fake personas, fake reviews, or pretending to be an ordinary customer if you're not.
Your marketing team is also responsible for monitoring disclosures and ensuring your brand partners are transparent. That means tracking affiliate links, reviewing influencer content, and making sure the average consumer won’t be misled about what’s sponsored and what isn’t.
Who’s doing word-of-mouth marketing well?
Need some referral marketing inspo? Here are some examples of brands knocking it out of the park with WOM programs.
Regal Cinemas
Regal Cinemas has mastered the art of the double-sided referral bonus with its Regal Unlimited plan. Current Regal Unlimited subscribers can send a referral link to a friend or family member to give them one month of unlimited movies for free, and the referring customer also gets a free month. Customers are incentivized to share their referral link, and new subscribers get to try out the plan at no cost (popcorn not included).
Surly Bikes
Cyclists love to show off their builds and their adventures. Surly Bikes, which sells both parts and full bikes, knows this and leans heavily into this on its Instagram channel. The company takes advantage of Instagram’s collaborative post feature, which allows a piece of content to show up on two or more users' feeds. They’re able to reach cycling influencers by being tagged in customer posts, and cycling influencers can increase their reach by tapping into Surly’s impressive 227,000 follower base.
HigherDOSE
HigherDOSE didn’t launch with a massive ad campaign or influencer budget. Instead, the wellness brand created products like infrared sauna blankets, PEMF mats, and other biohacking spa tools so buzzworthy that celebrities started talking about them without being paid to.
Wellness tastemakers like Gwyneth Paltrow and Kelly Ripa have shouted out HigherDOSE in interviews, newsletters, and social posts, driving massive visibility through pure word-of-mouth. Why? Because the products are bold, unique, and perfectly aligned with the self-care routines of their target audience.
Key takeaways for in-house marketing teams
Trust beats targeting. Consumers trust word-of-mouth more than ads.
WOM isn’t one channel — it’s everywhere from DMs to Reddit to AI overviews.
Six triggers fuel sharing: social status, visibility, emotion, utility, cues, and stories.
Good referrals feel real. Pair talk-worthy moments with appropriate incentives.
Track what you can, but embrace the fact that organic sharing isn’t easy to attribute.
Stay ethical. Disclose relationships, avoid manipulation, and follow WOMMA and FTC rules.
