Check card eligibility for installments using the PaymentIntent confirmation response, which returns available installment plans when the issuer supports it for the card
Present available plan options (number of installments, monthly payment amount, total cost) to the cardholder before confirmation
Set the selected installment plan on the PaymentIntent using the payment_method_options.card.installments field before or during confirmation
Handle the payment confirmation response: the authorization covers the full transaction amount but the cardholder is billed in installments by their issuer
On refunds, understand that the issuer handles installment unwinding; submit a full or partial refund via the standard refund endpoint and the issuer adjusts the cardholder's plan
Display accurate installment terms in your checkout UI including APR if required by local consumer credit disclosure laws
Known gotchas
Installment plan availability is issuer-controlled and varies by country and card product; do not assume installments are available until the eligibility check confirms it
Partial refunds against installment transactions may be handled differently by each issuer; some will reduce remaining installments, others will issue a lump credit
In some markets (e.g., Mexico), installments are interest-free (meses sin intereses) but require specific merchant agreements with each card brand; without the agreement, the installment option will not surface
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