Speaking of Psychology - The psychology of spending, debt and budgeting, with Abigail Sussman, PhD

Episode Date: April 8, 2026

Buy now, pay later plans have skyrocketed in popularity in recent years, adding yet another variable to consider when making spending decisions. Abigail Sussman, PhD, discusses the psychological biases that influence how we spend, budget and borrow, including why splitting payments can make purchases feel more affordable, why we underestimate irregular expenses, and why many people carry debt even when they have savings. She also shares research-based strategies to help you make more deliberate choices and better manage your money. Learn more about your ad choices. Visit megaphone.fm/adchoices

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GoogleFi Wireless is not subject to data traffic deprioritization during times of high network usage. If you've bought anything in the last few years, you've probably encountered a new way of paying for your purchases. When you check out at the grocery store or hit pay now in your online shopping cart, you're asked, do you want to pay in full today or split your purchase into four installments to be paid over time? The prevalence and popularity of these buy now pay later services has surged in recent years. One 2025 survey found that more than half of Americans had used. the Buy Now Pay Litter Service, such as After Pay, Clarnah, or Zip in the prior 12 months. Today we're going to explore the psychology of spending, budgeting, and debt, including

the rise of Buy Now Pay Later services. How does the way we pay for a purchase affect our spending decisions? Why is it so easy to overspend? Why do people not pay off their credit card balances even when they have the cash? And how can we make better financial decisions in an increasingly complex and tempting financial landscape. Welcome to Speaking of Psychology, the flagship podcast of the American Psychological Association that examines the links between psychological science and everyday life.

I'm Kim Mills. My guest today is Dr. Abigail Sussman, the V. Dwayne Rath Professor of Marketing at the University of Chicago Booth School of Business. She studies the psychological biases that lead people to make errors in budgeting, spending, borrowing, and investing. Her research investigates questions at the intersection of psychology, economics, and finance,

with the aim of improving people's financial well-being. Her work has been featured in top academic journals, including the Journal of Consumer Research, the Journal of Experimental Psychology, and the Journal of Finance, as well as popular media outlets, including National Public Radio, the New York Times, and the Wall Street Journal. She recently spoke to APA's magazine Monitor on Psychology for an article about the psychology of debt and buy now pay later loans. Dr. Sussman, thank you for joining me today. Thank you so much for having me.

I'm really happy to be here. So I want to start by talking about what I mentioned a moment ago in the introduction, which is these buy now, pay later services that have spiked in popularity. What do we know about how they change people's spending behavior? Well, so one of the things that we know is that they lead people to spend more. And we can think about what happens in terms of the underlying psychological. here, which is that you go to make a purchase and you learn that instead of having to pay $100 today, you only have to pay $25.

And all of a sudden, the purchase that seemed really expensive suddenly feels very affordable. And if you don't really stop to think through what the implications are, you think actually maybe I can buy four different things for $25 and spend the same $100 that I had intended to spend today for the single product. And so as a result, it leads us to spend more without really feeling like we're doing so. Well, why does buying something with installment payments feel different from just putting it on a credit card? You know, I think that one of the main characteristics that differentiates the Buy Now Pay Later plans is the sticker price. And so when you pay for something using a credit card, the cost that is displayed to you is the full cost of the product.

when you buy something using a buy now pay later plan, what you're really seeing is the cost of the payment that you're making today. And so even if for the credit card, you might actually put something on your credit card and not pay any of it off for, let's say, a month, but you're very aware of the fact that the amount that you're going to be paying is the full price and that in some sense you're borrowing the full price of the item versus the buy now pay later plan, you're focused on the amount that you're paying today, and it really dissociates the amount that you're going to be paying in the future periods. Let's stepping back for a minute. Your research has looked more broadly at why we overspend and make

less than optimal financial choices. And one thing you've found is that we aren't very good at accounting for unexpected expenses in our budgets. Can you talk about that work? Yeah, for sure. So I guess I would say why we maybe overspend relative to what we would expect to spend. It's hard to say what's optimal in that in some cases we also are underspending. So we don't always give ourselves the pleasures that maybe would be beneficial. So it sort of depends on who you are and who you're, what your financial situation is, what the optimal level is. But often we overspend relative to what we expect or relative to what we would plan for ourselves. And I think those cases, we could really describe this sort of suboptimal. And so a lot of this research started actually before I became

a psychologist. I was working in equity research and studied airlines. And so one of the things that I noticed in that context was my job was basically to predict the financial statements of firms in future periods. And for airlines, if you were trying to predict what this airline was going to spend in the next period or the next quarter, what you would do is you would try to think about what did they spend in the past quarter or over the past several quarters. And then you would actually, you were specifically instructed from accounting rules to pull out these unusual expenses. So if you were an airline, let's say that there was some sort of restructuring that happened or planes were grounded or there was a hurricane or a strike or any number of different things that

were unusual. Okay. So you were instructed. as the financial analyst to pull those items out and report them separately. And so when you were making your predictions, the intent was to exclude those items from what you would expect would happen in the next period. And this always seemed very interesting to me because it seemed like, well, in real life, these events keep recurring. And even in the context of the airlines at that time, something kept recurring. And like you wouldn't have a strike again the next period.

maybe there would be a hurricane the next period or something damaged to the airline fleet or whatever it was. And that led me to investigate the same kind of prediction error in the context of consumers. And so what I've found in my research is that people are very bad at predicting the idea that something unusual will happen when they don't know what that's going to be. And so maybe like I'm spending extra money this quarter because it's Halloween and I have Halloween decorations. and candy and whatever else. And then suddenly it's like, you know, now it's the next month and it's Thanksgiving, but Thanksgiving doesn't happen again in December. In December, it's Christmas. And then in January, it's New Year's and in February it's, it's Valentine's Day. And so each one of these times,

it's like, well, no, Valentine's Day is not happening again in March, right? So, and each time you're right that that particular expense is not going to recur. And so I think that there's something, thing around the psychology of it's it's very easy to think about what is the baseline set of expenses that we have. So am I going to predict my grocery bills? Yes. Like that's going to be sort of easy to predict my, you know, the cost of my mortgage or my rent. Like, yes, I'm going to do that. And the cost of like, you know, usually I go out to dinner, you know, three times a month and I'm going to plan for that too. So that stuff is sort of stable and it factors very much into our predictions. but what doesn't factor into these predictions are these outlier expenses.

And in some sense, as I think evidenced by this example from financial analysts, maybe they shouldn't because that particular expense isn't going to recur. But in practice, what happens is that when you think about this category of unusual expenses, there's likely to be something that will fill that spot. And so it's really good to leave a placeholder to say, here's the thing that I'm not going to expect. We're going to leave a buffer for that. Right. And do people tend to do that or is that just impossible?

I mean, you know, there were rules about you should have how many months of expenses in a rainy day fund just in case, one of those just in case things. Why is that such a problem for us? So I guess there are two different things. One is like you can have money that's set aside for a rainy day fund. but the question is, should you be tapping into that or should you actually plan on having that be part of your budget? Right? Like, you shouldn't, you should have that as part of your rainy day fund. That's a separate question.

And some of us are able to set aside that money and some of us aren't. But the question is on a monthly basis, why do we need to tap into the rainy day fund? Why can't we just plan for that in our budget, right? Like, why can't we anticipate these expenses? And what we find, and so this is in research led by Chuck Howard, in terms of this expense, the sort of prediction error is that you can ask people basically repeatedly, how much did you spend last week? They'll say $100.

How much do you think you're going to spend next week? $80. Okay, a week later, how much did you spend last week, $100? How much you're going to spend next week? $80. And people actually will just keep doing this over and over again. And what happens is that people essentially are predicting their modal spending and they're failing to anticipate any of these sorts of outlier expenses.

Now, if you get people to stop and reflect on what do you think is going to be different next week and to pause and think through this, they are able to identify what those differences are likely to be. But at baseline, it's not what comes naturally to people. Instead, they're just going to think about what were the things that I spent money on last month, which of those are going to recur and sort of only project the ones that are going to recur. and sort of only project the ones that are going to recur going forward, and that's where you get this gap. And, you know, one of the other consequences of focusing on this is that people tend to actually spend more on these one-off expenses than they might otherwise because they think of them

as exceptional. And so if I think, you know, this particular kind of expense, it's like I'm buying a birthday present, for example, this only happens once a year. Well, then I can afford to spend more on it. And so it also licenses you again because I'm not thinking about it as a recurring expense. And so the cost is only one higher price rather than 15 higher prices if you think about the fact that similar kinds of expenses occur 15 times throughout the year. So how do stores and retailers take advantage of the psychological biases we experience when they're trying to sell us products? Yeah, so I think that that's a very broad question. And I think there are many different things that stores do in terms of, one is bringing this idea back to the buy now, pay later plans, which is really how do you think about the costs and the benefits and the timing. of various costs and benefits. And so to the extent that you can focus people on the benefits that they'll get today and the costs that will come later. So I'm advertising that you can get this

today and have a delayed payment. Another thing is just potentially increasing the extent to which products seem like they're necessary. And so here, companies can be very good at helping combine or bundle products together and advertise what might actually be something that's a superfluous product, but that feels like, well, if I'm buying this, I'll actually probably save money over time by buying this additional complement. So those are, I think, just two examples. In addition to just being so good at predicting things that you might want and suddenly feel like you actually need to have them. So I think firms have gotten very good at predicting their customers' needs to needs and wants and desires and increasingly sort of throwing in more tempting options together.

And of course, AI keeps pushing things at us whether we want them or not. So one day you go and you look at a pair of shoes and now for the next three weeks, all you see in your feet is shoes, shoes, shoes. And they're like, I guess I did want those. Or you left this in your card. You know, all of those kinds of little tips and tricks. You looked at this on eBay. It's still for sale.

You know, come back. The price just came down. down $100. Exactly. Right. And I think that the price just came down is another interesting one, right? Like, how do firms think about advertising discounts? How do firms take advantage of sort of a limited time opportunity, right? So I think from a scarcity perspective, you don't want to miss out on an opportunity, and that opportunity can be a discount as well. And that's something that, right, people get a lot of value from feeling like they've gotten a deal. And that's another place where we see, where we see stores taking, I mean, being very aware of what they're doing. The more you spend,

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When you want savings, not surprises. It matters where you stay. Hilton for the stay. We're going to take a short break. When we return, I'll talk with Dr. Sussman about keeping up with the Joneses and how people think differently about wealth and debt when they're comparing their own spending with their neighbors' spending. Now, you've also studied how people think differently about wealth and debt when they're comparing

their own spending to their neighbors' spending. How does social comparisons shape our spending and saving behaviors? Yeah. So one of the things I think that was the insight of this paper that you're mentioning with Raphael Batista and Jennifer Trueblood, one of the insights there is basically, that when we think about social comparison, there's been a lot of work for many, many, many, many years on conspicuous consumption, thinking about we observe what other people are purchasing, and we draw inferences from that. And similarly, we want to consume fancy cars, fancy clothing,

right, that we know other people are going to look at and they're going to think more highly of us, for example, for consuming those things. One of the things that is less visible and generally actually not talked about at all is not the consumption side of things, but the saving and debt side, right? And so we really don't know how much debt somebody has. We don't know how much money somebody has in their savings account. And I think that to some degree, this puts us as a society at a huge disadvantage because you end up at this keeping up with the Joneses for, in some sense, the things that are maybe the least important aspects of consumption, whereas the things that actually provide us with financial stability and feelings of financial comfort, which are really

important, are not going to be sending any sort of signal of status. And so what ends up happening is that we evaluate people based on their spending. And I think that the fact that if we look at what somebody else has spent, we don't have visibility into the debt that they took on, let's say. In our own spending, we're very aware of the debt. And so when we think about sort of evaluating how wealthy does this make me feel, I'm going to be very sensitive to how much debt I took on in order to make this particular purchase and not evaluating somebody else. And so this has the potential to actually really aggravate and exacerbate this conspicuous consumption cycle. Between inflation and job instability, a lot of people are feeling financially stressed right now.

How do stress and economic uncertainty change the way that people make spending decisions? Yeah. So this is, I think, a really important question right now. And I think that in many cases, it makes people more myopic. And so I'm going to be more focused on what is my budget this month. And I'm going to be really, focused on trying to stay within my means for, let's say, I would set specific budget categories. And on a day-to-day basis, make sure that I'm spending less. But I'm more likely to lose sight of the bigger picture financial goals. And so one of the things that we find is that people with lower incomes and more financial instability actually find budgeting also less pleasant and are less likely to do it.

But conditional on engaging in budgeting, people are checking their budgets more, right? So it becomes more of an exercise of making ends meet rather than thinking about striving for something better or thinking about longer-term financial goals, which is just one of the, I think just something that falls out naturally from the constraints and limitations. Another related piece of work looks at the effect of actually losing one's job on financial risk-taking. And in this work with Sam Hirschman and Jennifer Trueblood, we find that actually after losing one's job, people spend less overall, but actually the amount that they spend on something like, gambling or other kinds of risky financial behaviors decreases relatively less than other spending. And so what this suggests is that people really are hoping to make up for the amount that they've

lost in these kinds of financial shock kinds of experiences. So overall spending less, but still trying to remain in some sense like optimistic around this risk-taking behavior. Do you have advice for people who would like to do a better job of sticking to their budget? Are there, is anything in your research that suggests strategies that we can use in our everyday lives? For sure. So I think there are a couple of things. So one is trying to set a realistic budget in the first place. I think that's going to be key.

And so that includes things like either leaving a buffer for unusual kinds of expenses or one-off expenses. And you could think about rather than. going back and thinking on a category by category basis, how much have I spent in each month, let's say, look at your aggregate spending and try to make sure that your budget matches the aggregate level of spending rather than summing up from the bottom by category, if that makes sense, either by, you know, increasing the amount in each category or adding a separate bucket. Another thing is around this impulsivity and sort of buying based on the pair of shoes that was shown to you at each different website that you went to, right? And so

one of the things that's happened, I think, a lot is around just automating the purchasing process and reducing frictions for spending. And so if you, for me, like say, like, right, if I go online to any store, all of a sudden, the internet has my credit card information, like, my computer has my information stored in five different ways. And it used to be like you had to, well, it used to be, you had to take out cash from your wallet and you had to be in a store to make a payment. You thought a lot about what that payment was going to be right before you made it. It was psychologically costly in addition to the dollar cost to separate with that money. And now I don't even need to take out my credit card to make a payment.

I just have to keep sort of clicking through and everything is automatically filled in for me. And so to the extent that we can reintroduce frictions into our spending, this is something that's helpful. And so making rules for yourself could be, I'm only going to buy in person would be one kind of rule. That comes with other challenges, which is like now you're at the store and now you're tempted by all the different things in the store. So sort of going with a more concrete plan in that case. But I think just removing your credit card online, you know, taking it down from Google Pay. and Apple pay. These kinds of things will just lead us to pause and reflect and we can still buy all of the things that we want to buy, but really making sure that we've thought through these

decisions, I think is going to be one valuable component. And then the other is to try to be thoughtful about when we're spending. So setting aside specific times to be making purchases as opposed to either being online and sort of shopping out of, you know, different sorts of emotions or boredom or going to the supermarket even and you can go to the supermarket when you're starving or you can go to the supermarket when you've come with a plan. And if you go when you're starving, like probably you leave with a lot of Kit Katz and not necessarily the food that you needed.

And so going, right, and so being thoughtful, we sometimes think about this as, as spending in a cold state, like when your emotions are low and you're not in sort of the heat of the moment. So we can think about that from a hunger perspective would be the analog for a grocery store, but you can think about this from other perspectives as well, depending on what the kind of purchase is. But trying to sort of take the emotion out of the spending is another way to think about restraining our spending and staying within our budgets. There seem to be a lot of apps out there these days that promise that they're going to help you get your financial life in order. And, you know, I get all these ads for, I'm not going to name it because they're not a sponsor.

But there's a particular app that tells you, you know, you've got four subscriptions to Netflix and you haven't watched Hulu in six months. And I'll cancel these things for you. Do those apps really work for people? Or are we that sad that we don't know how much we're subscribing to at this point? We need something else, something external to tell us. I think that the topic of subscriptions is actually a big problem. People do not unsubscribe. So I actually think a lot of people have subscriptions that they are not paying attention to,

that they're not aware of, that are automatically renewing. it's incredibly difficult. I mean, I don't know incredibly difficult, but oftentimes, right, signing up for something is very easy and you frequently will click a button that says auto renew or you won't be allowed to sign up unless you agree to auto renewal. So I actually think the topic of apps is sort of, it depends on what the app is and how helpful it could be. Like surely there are apps out there that can be helpful for managing your finances.

I mean, one of the things that apps do is they also select on people who care and are focused on it, right? They bring your attention to these issues, which I think, again, can be very valuable. I think for many people, it's easy to lose track of it. And companies are not always reminding you before that payment comes due, right? Why would they? Why would they? Exactly. You've also looked at how people think about the tradeoff between savings and debt,

especially something that's called co-holding, I think I mentioned in the intro, people have credit card debt, but they also have money in savings and they could pay off that debt. Does this ever make financial sense? And if not, why is it so common? Yeah, for sure. So this is something that's quite common behavior. And there are cases where it could make financial sense. So for example, if you're worried that you won't have access to liquidity from your credit card in the future, then maybe you need that sort of savings buffer because that's the only way that you'll have cash to pay bills. That's the sort of thing that could make financial sense. I think for many people who are engaging in co-holding, that's not the case, right? They would have, if you paid down

your credit card bill this month, you could continue to borrow on credit the next month, for example. And I think there's also a question with co-holding of sort of how much money do you have in cash and how much money should you have in cash from a comfort or savings perspective. So I think that there's definitely complexity there, but I think that a lot of what happens with co-holding, and there have been many different explanations proposed largely within the economics literature, I think that there's also something psychological going on where we feel responsible for having money and savings, and we're able to, because of mental accounting, we mentally segregate savings in debt. So we don't think of it as having one pool of money, and that money is basically

right. Our savings minus our debt. Instead, we think of it as two distinct pools. And so our savings is on the right. Our debt is on the left. And to the extent that you think about these two things as distinct pools, well, what do people who are financially secure have? They have money and savings. And so if I want to feel responsible, I'm going to have money and savings too. And so this is something that I've worked on with work O'Brien looking at what happens. when the amount of the money that you have in savings is designated for different purposes. So if you think about this money that I've set aside in savings for something really responsible, so for my kids' education, for example, I'm not going to touch that.

And if some expense comes along, I'm going to instead borrow on my credit card because, of course, I'm not touching, you know, money that I've set aside for my kid or whatever it is. If I have money set aside for my vacation, I'll be more likely to draw that down. And so I do think people are able to segregate and say, like, yeah, it's bad that I have money in debt, but it's really important that I have money in savings. And what are these two things even have to do with each other? And so more recently in work led by Raphael Batista again, we've done some research where we've worked with a large bank in Australia and we've partnered with them to actually run experiments where we're able to send people. banking app notifications telling them that they have money in both savings and debt. And basically that this is a costly for them to do that their credit card debt is, you know, they're being charged high, you know, 15% interest, let's say, versus 1% interest that they're that they're getting on their on their savings accounts.

And so sending these sorts of in-app notifications. And what we find is that it actually has minimal effect on behavior. So it doesn't seem like most people are doing this sort of by accident, but instead it's quite deliberate. And so in more recent work, we're also looking into the idea that one of the things that we've noticed in terms of digging into transaction data around these customers is that the customers that tend to be co-holding tend also to be using their debit cards more. for transactions. And so this suggests that an additional factor beyond what I've already been talking about is that for people who want to be spending on their debit card in particular for everyday transactions, you need to have some kind of savings buffer around in order to spend on your debit card. And so it's actually, it's not the comfort with credit that allows these people to be coholding,

but instead it's almost a discomfort with credit of, right, I want to, I want to be more focused on the fact that I have this money and savings that's available. That can be the driver. Again, treating these two pools is like really distinct. Right, right. So just to wrap up, what are the big questions that you are still trying to answer? What are you working on right now? So great question.

There are a handful of different topics. One that I'll mention just because it relates to some of the earlier points that have come up. but is in terms of thinking about buy now pay later plans and wealth signaling these were sort of two different topics that came up earlier and one of the the projects that I've been working on has been looking at what happens when you are using a buy now pay later plan or any other form of payment method what are the kind of wealth signals that people derive from this and so typically we think about wealth signaling as being really around these highly conspicuous behaviors, or specifically purchases is sort of the most traditional version of this, right?

I buy a fancy car, for example. And these are also sort of long-lasting transactions, right? Or sort of you have the car and you're displaying it all day long to your friends. But what we're proposing in this research is that in addition to the purchases themselves, that actually the way that you make the purchase can send a way. wealth signal, both externally, let's say, to the retail, like to the store employee, but also internally can send a signal of status to yourself as well over how you feel about making the purchase. And so using the Buy Now Pay Later plan versus a credit card versus a platinum

amex card, actually the method of payment can make us feel differently about the expense, which can then have potentially downstream consequences for our likelihood of sort of continuing to use these methods and to return to the same stores going forward. Well, Dr. Sussman, I want to thank you for joining me today. This has been illuminating. Thank you so much for having me. Really fun conversation. You can find previous episodes of Speaking of Psychology on our website at speakingofpsychology.

Or on Apple, Spotify, YouTube, or wherever you get your podcasts. And if you like what you've heard, please follow us and leave a rating. If you have comments or ideas for future episodes, you can email us at speaking of psychology at APA.org. Speaking of Psychology is produced by Lee Wynerman. Thank you for listening for the American Psychological Association. I'm Kim Mills. Enjoy more ways to save at Ralph's, like low prices in every aisle. And when you download the Ralph's app, you can clip and save more with digital coupons every week.

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