Latest / Behavioral Economics with Fexingo: Decision Making, Bias, and How People Really Spend / Why Your Brain Treats a Round Number as a Trust Signal
Transcript
- Lucas: Luna, when you see a price tag that says $9.99, what's your gut reaction? Luna: Honestly? My brain says 'that's ten dollars but they're trying to make me think it's nine.' Why, is that the wrong response? Lucas: No, it's exactly the right response — but there's a twist. For decades, marketers have used charm pricing — ending prices in.99 — because it supposedly makes things feel cheaper. And it works in many contexts. But a growing body of research suggests that in certain situations, a round number like $10 actually triggers more trust. Luna: So round numbers are a trust signal? That's interesting. Where does that show up? Lucas: One of the clearest examples is in medical copays. A 2023 study from the University of Florida looked at how patients react to copay amounts. They found that when a copay was a round number — say $20 — patients perceived it as more fair and transparent than $19.99, even though the difference is a penny. The theory is that round numbers signal that the price isn't being manipulated to exploit you. Luna: That makes sense. If a doctor's office charges $19.99 for a copay, it feels like they're nickel and diming you. But $20 feels honest — it's a clean number. Lucas: Exactly. And it's not just healthcare. Think about taxi fares — or ride-hailing surge pricing. When a ride shows up as $15.00, you're less likely to question it than $14.87, which feels arbitrary and maybe even algorithmic. Round numbers give us a cognitive shortcut that says 'this price was set by a human who values clarity.' Luna: But isn't that the opposite of what we usually hear about pricing? For decades, the advice was always 'use.99 to boost sales.' Lucas: Right, and that advice works — for low-consideration purchases like a pack of gum or a can of soda. But when the purchase involves trust, fairness, or a relationship, round numbers outperform. The study I mentioned found that the effect is strongest when there's a perceived power imbalance — like between a patient and a healthcare provider, or a donor and a charity. Luna: So charities should use round numbers for suggested donation amounts? Like 'give $25' instead of '$24.99'? Lucas: Yes, and some of the most effective charities already do that. A well-known example is Smile Train — they use round suggested amounts like $30, $60, $120. And there's research showing that round numbers in charitable giving increase both the likelihood of donating and the average donation size, because donors feel the ask is straightforward. Luna: But luxury brands have been using round numbers forever. Rolex doesn't sell a watch for $9,999. It's $10,000. Is that the same mechanism? Lucas: It's related but slightly different. For luxury goods, round numbers signal quality and exclusivity. A $10,000 price tag feels deliberate and confident — it says 'we know what this is worth.' A price like $9,999 would feel like they're trying too hard to seem affordable. It undermines the brand's positioning. Luna: So.99 cents screams 'discount retailer,' while a round number whispers 'premium.' That's a neat distinction. Lucas: Exactly. And the fascinating thing is that this isn't just a marketing trick — it's rooted in how our brains process numeracy. We tend to perceive round numbers as more fluent, easier to process, which intuitively makes them feel safer. That fluency triggers a positive emotional response. Luna: But I can think of exceptions. Whole Foods — now part of Amazon — often uses prices like $3.99 or $5.99 for produce. Yet they're a premium grocer. Doesn't that contradict the theory? Lucas: Not necessarily. In the grocery context, the purchase is low-consideration — you're buying a tomato, not making a trust-based decision. So charm pricing still works there. But if you look at their prepared foods section or their catering services, you'll see more round numbers. The context matters. Luna: So the same brand can use both strategies depending on the product category? That's nuanced. Lucas: Right. And this is where it gets really interesting for digital subscriptions. When you subscribe to a service like Netflix or Spotify, the price is almost always a round number — $9.99, $14.99, $19.99. Wait, those aren't round numbers. Luna: Exactly — they're just-below. So why do digital subscriptions use.99? Isn't that a trust context? You're entering into a relationship. Lucas: That's the puzzle. One explanation is that in digital subscriptions, the.99 has become so conventional that a round number would actually look suspicious. If Netflix charged $10 even, you might wonder what they're hiding. So the charm pricing is the default, and breaking it would signal something unusual. Luna: So you're saying the context flips again — in a market where everyone uses.99, a round number is the outlier and triggers distrust. Lucas: Exactly. There's a 2021 paper in the Journal of Marketing Research that looked at this. They found that when a product category has a strong norm for either round or just-below pricing, deviating from that norm hurts consumer interest. So it's not that round numbers are always better or that.99 is always better — it depends on what the consumer expects. Luna: That makes sense. It's like there's a pricing grammar — you have to speak the language of your category. Lucas: Right. And that grammar can change over time. Twenty years ago, most fast-food menus used.99. Now, chains like McDonald's have moved to round numbers for many items — $1, $2, $3 menus. That shift probably signals a move away from a discount positioning toward a value positioning. It's subtle, but it's real. Luna: It reminds me of something I read about how consumers interpret 'odd' prices as signals of a sale. If a store normally prices items at round numbers and then puts a $14.99 price tag, it screams 'discount.' But if everything is $14.99, it's just the price. Lucas: That's a great observation. And it ties back to the trust point — because when a price deviates from the norm, our brain immediately asks why. If the answer is 'they're giving me a deal,' great. If the answer is 'they're trying to trick me,' then trust erodes. Luna: I've been thinking about something similar in my own spending. Like, when I donate to a friend's charity run, the suggested amount is usually $20 even. And I never question it. But if it were $19.87, I'd probably spend time wondering where that number came from. Lucas: Exactly. And that cognitive friction can be enough to make you abandon the transaction. So for charities, the round number isn't just about trust — it's about reducing cognitive load. You want the donor to think about the cause, not the price. Lucas: Now, here's where I want to bring this back to a broader point about behavioral economics. What we're really talking about is how our brains use heuristics — mental shortcuts — to make quick decisions about prices. And those heuristics are incredibly context-dependent. Luna: So the lesson for a business owner is: don't just default to.99. Think about what you're selling, who you're selling to, and what vibe you want to project. Lucas: Yes. And test it. Run an A/B test. For a low-consideration item,.99 might boost conversion. For a service that requires trust — like a financial planning subscription or a medical copay — a round number might perform better. Luna: That's practical advice. And it's one of those things that seems obvious once you hear it, but most businesses don't think about it. Lucas: Which is exactly why we do this show. Because pricing is one of those places where a tiny change — a penny — can have an outsized effect on behavior. And if you understand the psychology, you can make choices that actually serve your customers better. Luna: Speaking of serving listeners better — we keep this show ad-free. No sponsors, no interruptions. That's a choice we make because we think the content should speak for itself. Lucas: Yeah, and if you find value in these conversations — maybe one of those pricing insights saved you some money or helped you think about your own business — we'd love if you considered supporting the show. It's buy me a coffee dot com slash fexingo. That's buy me a coffee dot com slash fexingo. Luna: And to be clear, no pressure. Just if the economics walk has made something click for you. Lucas: Alright, back to pricing. One last angle I want to touch on: how this plays out in the digital marketplace. On Amazon, most third-party sellers use.99 pricing. But in 2022, a study from the University of Chicago found that the top 1% of sellers — the most reputable ones — were more likely to use round numbers. Luna: So reputation changes the pricing grammar. If you're established, you can signal confidence with a round price. Lucas: Exactly. And for a new seller, a round number might look arrogant. So they stick with.99 to blend in. It's like a linguistic marker of status. Luna: That's a great way to put it. Pricing as language. Lucas: Right. And like any language, it evolves. I suspect we'll see more round numbers in digital subscriptions as the market matures. Already, some SaaS companies — like Basecamp — use round pricing: $99 a month, not $99.99. It's a subtle signal that they're not playing games. Luna: So the trend might be toward transparency. Which is reassuring, honestly. Lucas: It is. And it shows that behavioral economics isn't just about manipulation — it's about understanding human decision-making so you can design systems that work better for everyone.