The Economics of Buy Now, Pay Later

You're checking out online. A jacket. $180. Then a button appears just below the price: 4 payments of $45. 0% interest. You click it without a second thought.

That split-second decision is worth billions of dollars to someone. Just not you.

Buy Now, Pay Later (BNPL) has quietly become one of the most successful financial products of the last decade. In Canada alone, the market hit $7.5 billion USD in 2025 and is projected to reach $11.3 billion by 2030. Globally, the BNPL market reached $560 billion in gross merchandise volume in 2025, and user adoption is on track to surpass 900 million people by 2027. Klarna went public in 2025. Affirm absorbed Canada's own PayBright back in 2021.

This isn't a trend anymore. It's infrastructure. And if you've ever clicked "pay in 4," it's worth understanding the machine you just opted into.

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What BNPL Actually Is (The Short Version)

The core model is simple: a BNPL provider like Klarna or Affirm steps in at checkout and pays the merchant in full, upfront. You then repay the BNPL company in installments: typically four equal payments spread over six weeks, with no interest, as long as you pay on time.

No credit card required. Minimal friction. Approval in seconds.

Affirm entered Canada by acquiring PayBright in January 2021, and Klarna integrated directly with Apple Pay for Canadian users in October 2024. Between the two of them, they're embedded at thousands of Canadian retailers, from Sporting Life to Sephora to Indigo.

The question most people never ask: if it's free for me, who's actually paying for this?

The Economics: Why Merchants Willingly Pay Up

Here's the core mechanic that makes BNPL viable: the merchant pays, not you.

Every time a Klarna or Affirm transaction goes through, the merchant hands over a percentage of the sale. Klarna charges merchants between 3.29% and 5.99% per transaction plus a $0.30 flat fee. Affirm runs roughly 3–6% depending on the product. For context, a standard Visa or Mastercard processing fee runs about 1.5–3%. BNPL is meaningfully more expensive for merchants.

So why do they pay it? Because the math works out in their favour.

Research published in the Journal of Marketing found that BNPL adoption is associated with roughly a 10% increase in purchase amounts and a 9 percentage point increase in purchase likelihood. A separate analysis found merchants can see average order value increases of 20–40% when BNPL is offered at checkout. A merchant paying 5% to Klarna on a $200 order that wouldn't have existed without BNPL is still ahead.

Think of it this way: BNPL companies are essentially selling merchants a conversion tool dressed up as a payment method. The merchant outsources the credit risk and pays a premium for the privilege of closing more sales.

The Psychology Engine: Why You Spend More

This is the part that matters most for understanding why BNPL took off the way it did.

When you pay $180 upfront, your brain registers a $180 loss. When you see "$45 every two weeks," something different happens psychologically. Researchers call this payment salience: the psychological weight or "pain" attached to a purchase. BNPL is specifically engineered to reduce it.

A 2025 study in the Journal of Retailing found that presenting installment prices directly lowers consumers' perception of how expensive a purchase is, not the actual cost, just how expensive it feels. More installments, or a smaller first payment, amplifies the effect. The product doesn't change. The price doesn't change. Only the framing does, and that framing drives measurably different spending behaviour.

There's also a concept from behavioural economics called present bias: humans systematically overvalue immediate rewards and undervalue future costs. BNPL is a present-bias delivery mechanism. You get the jacket now. The cost is future-you's problem, spread out into four tidy little payments that each feel trivially small.

A systematic review of BNPL research published in late 2025 summarized it clearly: BNPL's mechanisms; installment framing, urgency cues, and perceived affordability, consistently reduce payment salience and increase impulsive purchasing. The effect is strongest among younger consumers with smaller historical basket sizes. That's not a coincidence. That's the target demographic.

How Klarna and Affirm Actually Make Their Money

The "it's free" perception is technically accurate for the standard pay-in-4 product, if you pay on time. But the business model runs on more than merchant fees.

Klarna's revenue stack looks like this:

• Merchant fees (primary): 3.29–5.99% per transaction: the core of the model
• Late fees: $7 charged after 10 days if a payment is missed, capped at 25% of the order value
• Extended financing interest: For larger purchases paid over months, Klarna charges consumer interest
• Advertising and data: Klarna operates a shopping platform with 18 million monthly active users. Merchants pay for premium placement and access to Klarna's behavioural data. In a widely-cited industry moment, Affirm CEO Max Levchin publicly described Klarna as having "an advertising engine underneath that resells that user to other merchants". Klarna disputed the characterization, noting ads represented about 10% of revenue, but the revenue line exists and has grown faster than the rest of the business

Affirm runs a different playbook:

• No late fees (genuinely, it's a meaningful differentiator)
• Merchant fees as the primary revenue driver
• Interest on longer-term financing: Affirm offers plans from 3 to 36 months, with APRs ranging from 0% to 30% depending on creditworthiness. That upper end is higher than most Canadian credit card rates (verify current Canadian-specific APR range before publishing)

The philosophical gap between the two companies is real. Affirm only makes money when you successfully repay, its incentives are aligned with your repayment. Klarna has late fees and a growing advertising engine that monetizes your attention regardless of whether you miss a payment. Neither model is inherently predatory, but they're structurally different.

The Invisible Debt Problem

One of the more underreported dynamics of BNPL's growth is how it interacts with the credit system, or more accurately, how it largely doesn't.

Most BNPL products use a soft credit check at the point of approval, which doesn't appear on your credit report. Affirm reports some loans to bureaus depending on the product; Klarna's reporting is inconsistent. This means you can carry multiple BNPL balances simultaneously across multiple providers, and none of it shows up when a lender evaluates your creditworthiness.

If you're wondering how that affects your credit profile, our guide on building credit from zero and our breakdown of how credit scores actually work are worth a read.

The scale of this gap is significant. A 2022 analysis found that 63% of BNPL borrowers carried multiple simultaneous BNPL loans, and 33% had loans across multiple BNPL firms at the same time. None of that appeared in traditional credit bureau data. A lender approving you for a credit card or apartment lease is looking at a credit report that may not reflect what your actual monthly obligations look like.

The late payment picture is also worse than most people assume. As of 2025, roughly 34–41% of BNPL users report having missed a payment in the past year, with Gen Z users hitting 51%. And a 2025 survey found that more than 60% of BNPL users mistakenly believe paying on time builds their credit score, while only 13% correctly know it doesn't. That's a significant gap between perception and reality for a product being used by tens of millions of people.

In Canada, regulators are starting to catch up. In October 2024, Quebec consumer rights group Option Consommateurs released a report calling for federal regulation of BNPL, specifically flagging unclear contract terms and unexpected fees. The Financial Consumer Agency of Canada (FCAC) has increased its scrutiny of the sector. The regulatory frameworks in the UK and Australia, both further along than Canada, are being watched closely as models.

One $180 transaction, three completely different economic experiences. The merchant pays to use BNPL. The consumer defers the cost. The BNPL company earns on all three layers.

Where This Is Going

BNPL's next phase isn't about fashion checkouts. It's about embedding into every major spending category.

Healthcare, education, home improvement, and travel are all active growth markets for BNPL providers. Klarna and Affirm are both pushing into everyday spending through physical and virtual card products, and it's working. A 2025 survey found that 25% of American BNPL users had used it for groceries, up from 14% the year prior. Klarna partnered with DoorDash in 2025 to let customers BNPL food delivery. The goal is to become the default payment layer for anything, not just a $200 jacket.

In Canada, this expansion is already visible. Klarna's Apple Pay integration brought BNPL into any in-person retailer that accepts contactless payment. As of February 2025, over 560 Canadian merchants had Affirm embedded at checkout, and Sezzle was active at over 2,500 Canadian merchants. As these products move from occasional purchases into habitual everyday spending, the behavioural dynamics, reduced payment salience and present bias apply to a much larger share of your financial life.

The Klarna IPO in July 2025, which opened 30% above its $40 listing price and valued the company at nearly $20 billion, WAS a market signal. The global BNPL market is forecast to expand at a 10.2% constant annual growth rate through 2030, reaching roughly $912 billion in GMV. Investors are betting the payment infrastructure BNPL companies have built will become sticky enough to justify that growth at scale.

The further right you move, the more the "pain of paying" is psychologically removed from the moment of purchase, and the more research shows people spend. BNPL sits at the low end by design.

So Is BNPL Good or Bad?

Honestly: it depends on how you use it.

Used deliberately, BNPL can be a legitimately useful cash flow tool. If you have a $400 expense and your next paycheque covers it comfortably but is two weeks out, splitting it into installments with zero interest is a reasonable decision. It's functionally equivalent to a short-term, interest-free loan, which isn't a bad thing.

The problem isn't the product. It's the architecture around the product. BNPL is not designed to help you manage existing spending more efficiently. It's designed to expand your spending. The merchant fees are justified by the higher basket sizes. The entire business model depends on you buying more than you would have otherwise.

That doesn't make it predatory, but it does make it worth using with your eyes open. Every time you see that "4 payments of $x" button, you're looking at the output of a carefully engineered system. Understanding the economics behind it is the first step to deciding whether it works for you, or just for everyone else in the transaction.

TL;DR

• BNPL providers like Klarna and Affirm pay merchants upfront and collect repayments from consumers in installments
• Merchants pay 3–6% per transaction: more than credit card fees, because BNPL increases average order values by 10–40%
• You spend more because splitting payments reduces the psychological "pain" of a purchase, this is by design
• Klarna earns through merchant fees, late fees, and ad/data revenue; Affirm earns primarily through merchant fees and interest on longer-term plans (no late fees)
• Most BNPL activity doesn't show up on your credit report. 60%+ of users incorrectly believe it does
• 34–41% of users miss at least one payment per year; Gen Z hits 51%
• Canadian regulators are starting to scrutinize the space; expect more disclosure requirements in coming years
• Used deliberately, it can be a useful zero-interest cash flow tool; used passively, it's a system engineered to grow your spending
• Be careful out there ladies and gents.

Disclaimer:

This article is for educational purposes only and does not constitute financial advice. BNPL product terms, fees, and availability change frequently. Verify current details directly with providers before making financial decisions. Some figures referenced are sourced from U.S. market data and may not reflect Canadian-specific conditions exactly.*