A customer disputed a Shop Pay Installments order. Who handles it?

1. Affirm handles the dispute, not Shopify's chargeback page. Shopify's help says a customer whose payment was captured can open a dispute with Affirm.
2. Affirm emails your Shopify store owner. Shopify's help says you do not receive a notification in your Shopify admin.
3. You have 15 days to reply directly to Affirm's email with any evidence you want to provide.
4. After that, Affirm resolves the dispute within another 15 days and holds the disputed funds for the 30 day period.
5. If Affirm decides for you, the funds go back to the bank account you use for Shopify Payments. If it decides for the customer, they are returned to the customer, with no additional cost to you.

Source: Shopify Help: Shop Pay Installments FAQ; Affirm Docs: About Disputes API V3; Affirm Docs: Submit dispute evidence, read 4 October 2026.

1. Check the inbox of your Shopify store owner email. That is where Affirm writes, not your admin.
2. Find the order in Shopify: go to Orders and search for "Shop Pay Installments" to list orders placed this way.
3. Reply directly to Affirm's email with your evidence within 15 days.
4. Keep a copy of what you sent. Shopify's page does not describe a second chance to add evidence.

Neither Shopify's page nor Affirm's developer documentation gives a list of what Affirm wants to see, so nothing below is Affirm's own list. These are the usual building blocks, taken from Shopify's evidence lists for card disputes, plus the details Affirm's API says it records (shipping, contact with the customer, returns, cancellation). Send what is true and ask Affirm if you need to know whether it wants more.

• The order record: date, items, amount, and the customer's details on the order
• Shipping and tracking information, with the delivery date and address
• Your refund and return policies as the customer saw them, and where
• Messages with the customer about the order, including any about a return or refund
• Proof of any refund you already issued, with date and amount
• The dates the customer first and last contacted you, and whether a return was sent back and received (Affirm's API records these)

What Affirm's own developer documentation adds

• Affirm's Disputes API V3 reference lists these dispute reasons: cancellation or return not processed, incorrect amount, product not received, product unacceptable, cancellation not processed, and return not processed. The page is for developers, but it shows the questions a dispute turns on.
• Each dispute carries a "response due by" date and a status. The statuses that matter are "action required: merchant", "no merchant action needed", and closed in the customer's favour, the merchant's favour, or partly in the customer's favour.
• When evidence is submitted through the API it is a comment, one or more files, and optional structured details: the carrier and tracking number; whether the customer contacted you before the dispute (already contacted, no contact, no response) with the first and last contact dates; whether the item was returned (all, partial, none, or not accepted) with the return date and method; and the cancellation status and date.
• Affirm says it now collects details from the customer when a dispute is opened, such as return information and when the customer first contacted the merchant. It is worth having your own dates ready to compare.
• The 15 day reply window comes from Shopify's FAQ. The Affirm page we read does not state it, so use the due date in Affirm's email.

Plain text. Replace every [bracket] with a fact from your records and delete any line you cannot back with a file.

Subject: Dispute for order [order number], [Affirm reference if the email gives one]

Hello,

This is our response to the dispute on order [order number], placed on [date] for [amount].

What was ordered: [items]
What happened: [one or two plain sentences, only facts you can show]

Delivery: shipped on [date] with [carrier], tracking [number], delivered on [date] to [address]. Attached: [file name].
Policy: our [return or refund] policy at checkout says "[exact quote]". Attached: [file name].
Contact with the customer: [date and what was said, only if you have the message]. Attached: [file name].
Refund: [if you refunded, the date and amount. Attached: file name. If not, delete this line.]

We ask that the dispute be decided in our favour.

[Name], [store name]

Never state anything you cannot prove. Every sentence in the response should point to a file you can attach. Delete any line you have no file for.

• Waiting for a notification in the Shopify admin. Shopify's help says there is none for these disputes.
• Replying after the 15 days. Affirm then moves to resolve it within another 15.
• Sending evidence that you cannot back with a file, or claiming contact with the customer that you cannot show.
• Refunding to end it and expecting the fee back. Shopify's help says the Shop Pay Installments transaction fee is not returned when you refund an order.

Will I see the dispute in my Shopify admin?

No. Shopify's help says Affirm emails your Shopify store owner and you do not receive a notification in your admin. Check that email address.

How long do I have to answer?

Shopify's help says 15 days from the dispute email to reply directly with evidence. Affirm then resolves within another 15 days.

Who holds the money while it is decided?

Per Shopify's help, Affirm holds the disputed funds during the 30 day period.

What if I lose?

Shopify's help says the disputed funds are returned to the customer and there is no additional cost to you.

Can I just refund the customer instead?

You can refund, but Shopify's help says the Shop Pay Installments transaction fee is not returned to you when you refund. If a customer returns an item and has paid interest, that interest is not refunded to them either.

• A customer opened a Klarna dispute. How do I respond?
• They filed a chargeback after I refunded them. What do I send?
• A buyer opened a PayPal dispute. How do I respond?
• A Stripe dispute on my Shopify store: where do I submit evidence?

We read Affirm's developer documentation (the Disputes API) but found no merchant-facing guide that states what Affirm accepts as evidence or confirms the 15 day window, so those points rest on Shopify's FAQ only. How a dispute email looks is not described in the sources. Rules and deadlines can change, so use the due date and form on your own dispute.

The Chargeback Evidence Checklist, or its ready text to paste into ChatGPT, asks for your dispute reason and lists the proof to gather. Or pick the reason on the chargebacks page.

The kit now has six fill-in response letters for Word or Google Docs (one per reason), evidence checklists, worked examples and a one-page Start-here guide, plus an optional ready text for ChatGPT or a similar assistant that fills the letter in for you. The Chargeback Response Kit and the free Chargeback Evidence Checklist are written around Shopify's chargeback reason names: Fraudulent, Unrecognized, Product not received, Product unacceptable, Subscription canceled, Duplicate, Credit not processed and General. The Writer's README says it also handles inquiries, Shopify Protect orders and orders that were already refunded. Its response structure carries over to other payment methods, because the questions a bank asks are similar. Where and how you submit differs, and we have not tested the skill against Affirm's dispute email process. Check the form's own limits before you paste anything in. What carries over to PayPal, Stripe and other processors: the way the response is built (what happened, evidence as numbered exhibits, the policy quoted word for word, dated contact with the customer, nothing you cannot back with a file) and the evidence ideas for each kind of claim. The fill-in letters follow Shopify's reason names, so for another processor pick the letter for the closest reason and use it to organise your facts. What does not: the reason names, the deadlines, the evidence field names and where you submit, which belong to each processor, so check them against that processor's own page above.

Before: a merchant sent delivery photos against a fraud dispute and lost.
After: a verdict (weak, fight only if cheap), what the bank actually asks, and what to gather instead.

It is also one of the six helpers in the Store Ops Pack, $29.

Send the dispute reason, the amount, the due date and the evidence you hold, with no card or customer data. We reply with what looks strong, what is missing and whether accepting may cost less. Free, no call, no sign-up. We cannot promise a day, and nobody can promise how a bank or payment provider will decide.

Kai Ventura, Pro Skill Packs

General information from the public sources above and our own checklists. It is not legal advice, and no response can promise how a bank or payment provider will decide. Pro Skill Packs is not affiliated with, endorsed by or sponsored by Shopify Inc., Affirm, Klarna, PayPal or Stripe. All chargeback pages.