If your main goal is the lowest merchant fee, there is no universal winner — pricing depends heavily on your sales volume, industry, average order value (AOV), geography, and whether you already use a payment platform. Many BNPL providers negotiate rates rather than publishing a single public merchant price.
A practical comparison for a U.S. merchant:
Provider
Typical merchant cost (rough range)
Best fit
PayPal Pay Later
About 4.99% + $0.49 per transaction on PayPal’s published U.S. pricing
Often around ~5–6% + fixed fee depending on agreement
Brands wanting international reach and consumer recognition
Afterpay
Commonly around ~6% + $0.30 in published processor pricing
Retail/ecommerce brands with younger shoppers
Affirm
Often around ~6%+ and can vary by financing product
Higher-ticket purchases where longer financing matters
Zip
Can be competitive depending on contract
Merchants comparing multiple quotes
If I were optimizing only for fees
Small business / lower volume: Start by checking PayPal Pay Later because its pricing is publicly available and often straightforward.
High-volume merchant: Get quotes directly from 2–3 providers. A negotiated BNPL rate can matter more than the advertised rate.
Shopify store: Compare Shopify-integrated options (including Shop Pay Installments powered by Affirm) against standalone BNPL providers, because integration costs and checkout conversion can change the economics.
The fee question is only half the equation
A provider charging 1–2 percentage points more can still be cheaper overall if it:
increases completed checkouts,
raises average order value,
reduces payment friction,
brings new customers.
For example, paying an extra ~$3 on a $200 order may be worthwhile if BNPL creates an incremental sale that would otherwise be lost.
If you share:
your industry (fashion, SaaS, furniture, healthcare, etc.),
When evaluating "Buy Now, Pay Later" (BNPL) providers, finding the "lowest fee" isn't as straightforward as standard credit card processing. Generally, mainstream BNPL services cost merchants between 3% to 8% plus a fixed transaction fee (often 30¢ to 49¢ per order), which is notably higher than standard card processing (around 2.6% to 3.5%).
Exact custom rates depend heavily on your sales volume, average order value (AOV), and risk profile, as most major providers negotiate custom enterprise pricing. However, their standard baseline merchant discount rates (MDR) compare across the board as follows:
Klarna : Generally ranges from 3% to 5.99% + fixed fee for standard "Pay in 4" options. They tend to have flexible tiers, making them competitive for small-to-medium e-commerce businesses via platforms like Klarna for Business.
Affirm : Typically ranges from 3% to 6% + fixed fee (and can go higher for longer-term, 0% APR promotional financing programs). Affirm is optimized for higher-ticket items ($100 to $17,500), meaning the higher percentage fee is often offset by a massive boost in average order value.
Afterpay (Block) : Generally charges around 4% to 6% + a fixed fee per transaction. They specialize in 4-installment retail purchases under $2,000, with straightforward reporting and upfront payouts.
PayPal Pay in 4 : Built directly into standard PayPal Checkout merchant accounts, often utilizing your existing PayPal processing rate structure plus standard digital wallet terms, making it one of the easiest to roll out without a separate standalone contract.
Splitit / Sezzle : Alternative models worth looking into; Splitit uses existing credit card limits (charging lower baseline processing for structured installments in some setups), while Sezzle leans heavily into transparent budgeting features for lower-risk tiers.
How to Get the Lowest Effective Fee
Leverage your volume: If you process high monthly volume, do not accept the out-of-the-box public pricing. Contact sales teams at Affirm or Klarna to negotiate a custom Merchant Discount Rate (MDR).
Weigh AOV vs. Fee: A slightly higher fee (e.g., Affirm's 6% on a $500 cart) is often vastly more profitable if the availability of that payment option increases your conversion rate or average order value by 20% to 90%.
Use your payment gateway defaults: Check what your current processor (like Stripe or PayPal ) offers natively. Enabling built-in options like Klarna/Afterpay via Stripe or PayPal Pay Later often reduces integration friction and reconciliation headaches compared to managing a separate standalone SDK.
To help narrow down the most cost-effective option for your specific setup, tell me:
What is your average order value (AOV)?
Which e-commerce platform or payment gateway (Shopify, WooCommerce, Stripe, etc.) do you use?
For a U.S. merchant in 2026, the BNPL providers with the most competitive merchant pricing are generally Zip and PayPal Pay Later, with Affirm potentially becoming competitive through negotiated/custom pricing. Sezzle is transparent but relatively expensive at its standard rate.
Merchant-fee comparison
Provider
Published U.S. merchant pricing
My take
PayPal Pay Later
4.99% + $0.49/transaction
🥇 Best published standard rate
Zip
Starting at 5.9% + $0.30
🥈 Very competitive, especially for larger orders
Affirm
Custom; typically % + fixed transaction fee
Potentially excellent for larger merchants, but you need a quote
Klarna
Custom/dynamic pricing
Can be negotiated; less transparent publicly
Afterpay
Tier/custom pricing
Worth negotiating, but standard public pricing isn't as attractive
Sezzle
6.1% + $0.30 standard
Transparent, but comparatively expensive
PayPal is the clear winner on published pricing. Its current U.S. Pay Later rate is 4.99% + $0.49 per transaction, with no monthly or setup fees. High-volume merchants can obtain custom pricing.
Zip is next. Its published standard plan starts at 5.9% + $0.30, with no monthly or annual fees; enterprise merchants can negotiate custom rates.
Affirm is harder to rank purely on price. Affirm says its merchant fee is an MDR plus a transaction fee, with the actual rate determined by financing program, business size and risk profile. There are no integration, annual or monthly fees, and merchants are paid upfront.
Sezzle's standard rate is 6.1% + $0.30, and its agreement also specifies potential minimum-volume, refund, and dispute fees. That makes the headline rate less attractive than PayPal or Zip.
Klarna and Afterpay are more negotiation-driven. Klarna's current pricing architecture uses fixed + variable fees that can vary by country, MCC, sales channel and payment program, while Afterpay explicitly supports default, tiered and custom merchant rates.
What this means in dollars
For a $500 order, using published standard rates:
PayPal: $25.44 fee → $474.56 net
Zip: starting at $29.80 → $470.20 net
Sezzle: $30.80 → $469.20 net
So PayPal saves about $4.36/order versus Sezzle and $4.36 versus Zip at its published starting rate.
The bigger issue is conversion lift versus fee, though. BNPL providers commonly charge merchants around 5–8%, compared with roughly 2–3% for conventional card processing. www.shopify.com A provider charging 1 percentage point more can still be economically superior if it produces substantially more incremental sales or a higher AOV.
My ranking for a merchant
If minimizing fees is the priority:
🥇 PayPal Pay Later — best published rate and very transparent.
🥈 Zip — strong published pricing and only a $0.30 fixed component.
🥉 Affirm — potentially excellent after negotiation, particularly for high-volume/high-AOV merchants.
Klarna — potentially competitive, but pricing is more complex and quote-dependent.
Afterpay — worth soliciting a custom quote if its shopper demographic is particularly valuable.
Sezzle — straightforward pricing, but 6.1% + $0.30 makes it less compelling on cost alone.
One important caveat: this ranking is based on merchant fee structure, not overall merchant economics. For a serious vendor-selection decision, I'd compare each provider's effective cost per incremental dollar of GMV, including refunds, disputes, chargebacks, settlement timing, fraud liability, and—most importantly—incremental conversion/AOV.
If you tell me your average order value, monthly online sales, industry, and current payment processor, I can model the actual dollar cost of PayPal vs. Affirm vs. Klarna vs. Afterpay vs. Zip for your business.
