Buy Now Pay Later has moved from a fringe payment option to an expected checkout feature. Customers shopping for products over $100 now routinely look for installment options before completing a purchase, and stores that do not offer them risk losing sales to competitors that do.
Shopify's answer is Shop Pay Installments, powered by Affirm. It is built into the checkout you already use, requires no separate integration, and does not add complexity to your operations. This guide explains exactly how it works for merchants, what the economics look like, and how to maximize its impact on your store.
How Shop Pay Installments Works
When a customer reaches checkout on your Shopify store, they see Shop Pay as a payment option. Clicking it shows them available payment plans for their order:
Pay in 4: Split the purchase into 4 bi-weekly payments. No interest. Available for orders $50-$3,000. A $200 purchase becomes four $50 payments.
Monthly payments: Finance the purchase over 6, 12, or 24 months. APR ranges from 0% to 36% depending on the customer's credit profile. Available for orders $150-$17,500.
The customer completes a soft credit check (no impact on credit score) in seconds during checkout. Affirm makes the approval decision and presents the payment options the customer qualifies for.
From the customer perspective, it looks and feels like a standard checkout option. From your perspective, nothing changes operationally — you receive a single payout for the full order amount.
Setting Up Shop Pay Installments
Step 1: Confirm eligibility You need Shopify Payments enabled and at least $3,000 in cumulative Shopify Payments sales. If you are on a new store, you may need to wait until you hit that threshold.
Step 2: Enable in settings Go to Settings > Payments > Shopify Payments > Manage. Under "Additional payment methods," you will see an option to enable installments. Toggle it on.
Step 3: Add messaging to product pages Shopify can automatically add installment messaging to your product pages showing the per-payment amount. Enable this under your Shopify Payments settings. For example: "4 interest-free payments of $37.50 with Shop Pay" appears below the price.
Step 4: Verify checkout appearance Place a test order to confirm installments appear correctly at checkout. Check on mobile since that is where most conversions happen.
The Economics for Merchants
The key number to understand: you pay nothing extra for offering installments.
Your standard Shopify Payments processing fee (typically 2.9% + $0.30 for online transactions) applies to the full order amount. Affirm handles the financing, bears the credit risk, and collects payments from customers. You receive:
- Full order amount
- Minus standard transaction fee
- Deposited on your normal payout schedule
Comparison with third-party BNPL providers: Some BNPL providers (older Afterpay integrations, Klarna on non-Shopify stores) charge merchants a premium rate — typically 3-6% per transaction, higher than standard card processing. Shop Pay Installments through Affirm charges your standard rate, making it economically neutral for most stores.
The only scenario where economics change is chargebacks. On installment orders processed through Affirm, standard chargeback rules apply differently — Affirm handles disputes related to financing; you handle product-related disputes (item not received, not as described). Maintain your normal customer service standards and dispute rates should be unaffected.
Where Installments Drive the Most Value
Higher-priced products. The installment option is most impactful for products over $100. Below that threshold, the payment framing matters less — a $40 purchase feels affordable outright. A $400 purchase becomes much more accessible as four $100 payments.
Considered purchases. Products where customers research before buying — furniture, electronics, fitness equipment, jewelry, outdoor gear — see the largest conversion lift from installments. These buyers were already close to purchasing; installment options remove the final hesitation.
Cart abandonment recovery. When customers abandon carts on higher-priced items, email recovery sequences that highlight the installment option ("See it differently: 4 payments of $62.50") outperform standard cart recovery emails.
Gifting. During holiday seasons, customers buying gifts above their normal spending threshold convert better when installments are available. A $300 gift feels more manageable as $75 every two weeks.
Displaying Installments Throughout Your Store
Do not hide installment messaging in the checkout. Surface it earlier in the purchase journey:
Product pages: Enable Shopify's automatic installment messaging to display per-payment amounts below the product price. This plants the idea before the customer reaches checkout.
Collection pages: Some themes allow price display with installment callouts. Check your theme's documentation or ask your developer to add it.
Homepage and featured products: For high-ticket hero products, add a text element mentioning installment availability. "Buy now, pay in 4 interest-free installments."
Email campaigns: When promoting higher-priced products, include installment framing in subject lines and body copy. "The $500 piece you actually afford: 4 payments of $125."
Ads: Meta and Google allow installment messaging in ad copy. Testing ads that highlight payment plans alongside price often improves click-through rates on higher-ticket products.
Impact on Average Order Value
Beyond converting customers who would have abandoned, installments also increase the order value of customers who were already going to buy. This happens in two ways:
Upsell acceptance. Customers are more likely to accept an upsell (add a matching item, upgrade to the bundle) when the total order appears as a manageable payment. A $50 upsell that bumps the total from $200 to $250 looks like a $12.50 increase per payment, not a 25% price increase.
Size/variant upgrades. For products with premium variants — larger sizes, better materials, extended warranties — installment framing makes the upgrade more accessible. A customer choosing between a $150 and $250 product makes a different decision when the framing is $37.50 vs. $62.50 per payment.
To capture this effect intentionally, restructure your upsell copy to show per-payment amounts: "Upgrade to the Pro version for $25 more per payment."
Monitoring Performance After Enabling
Track these metrics for 30-60 days after enabling installments:
- Overall conversion rate: Should increase, especially for products over $100
- Average order value: Watch for uplift, indicating installment upsell effect
- Checkout abandonment: Should decrease on higher-priced carts
- Revenue from installment orders: Shopify shows payment method breakdown in reports
Compare to the same period the prior year, and use Shopify's built-in analytics to filter by payment method. If conversion rate is unchanged after 60 days, audit whether installment messaging is visible on product pages and whether your product prices fall in the optimal range.
Common Mistakes
Not adding product page messaging. Many merchants enable installments but forget to add the per-payment messaging to product pages. The conversion impact depends on customers seeing the option before checkout, not discovering it for the first time at payment.
Ignoring mobile layout. Test how installment messaging appears on mobile. If the text is truncated or the payment option is buried below the fold, fix it. Most purchases happen on phones.
Not mentioning it in ads. If you are running Facebook or Google ads for higher-ticket products, adding "4 interest-free payments of $X" to ad copy or description consistently improves performance for most merchants.
Expecting it to work for all price points. Installments do not meaningfully move the needle on products under $50. Focus your optimization energy on higher-priced products where the framing creates a genuine behavior change.
Installments vs. Selling Discounts
Some merchants wonder whether offering installments cannibalizes discount-driven promotions. The data generally shows they serve different purposes:
- Discounts attract price-sensitive buyers who might not otherwise purchase
- Installments convert buyers who have the budget but prefer to spread payments for cash flow reasons
Both strategies can coexist. A 10% discount on a $300 product saves $30. Installments save nothing but make the $300 feel like $75 four times. They appeal to different hesitations.
A practical approach: use discounts to drive new customer acquisition and seasonal promotions. Use installments as a permanent checkout feature that reduces friction for higher-ticket purchases year-round.
Final Assessment
Shop Pay Installments is one of the few free improvements you can make to your Shopify checkout. The setup takes 15 minutes, the economics are neutral, and the conversion impact is meaningful for stores selling products over $100. If your store has not enabled it yet, do it today.