Mastercard Reason Code 4850: Installment Billing Dispute
In participating countries, the cardholder disputes an installment charge — for example claiming the installment plan was not what they agreed to, or that an installment was billed incorrectly.
Your strongest argument
The installment was billed exactly per the plan terms the cardholder accepted at purchase.
Evidence that wins a Mastercard 4850 dispute
- The installment plan terms the cardholder accepted at purchase
- Schedule of installments and the amount due for the disputed billing
- Records showing the installment was billed per the agreed schedule
- Proof of any credit issued if an installment was billed in error
Ordered strongest first — lead your rebuttal with the items at the top.
Source: Mastercard Chargeback Guide. The Mastercard rulebook defines this code and its dispute framework; the issuer decides every dispute and sets the exact deadline shown in your processor dashboard.
Not sure you have enough to win?
Run a free 60-second readiness check for Mastercard 4850. Answer a few yes/no questions and get a 0–100 score, a green/amber/red evidence checklist, and your exact response deadline — no signup.
How processors label this dispute
| Processor | What you'll see |
|---|---|
| Stripe | reason: subscription_canceled |
Where to pull this evidence
Prove the subscription was active, disclosed, and used when it billed. Here's exactly where the relevant records live in each processor dashboard — gather them free before you build your pack.
Stripe
Dashboard → Payments → Disputes (or the email alert from Stripe).
- AVS & CVC check results: Open the original payment → Payment details → "Checks" (CVC, ZIP, address).
- Customer email, IP, and device: Payment → Customer section and the "Risk insights" / Radar panel.
- Receipt / order confirmation: Payment → "Send receipt" or your order-management system; export the PDF.
- Refund history & reference IDs: Payment → Timeline shows any refunds with their re_… reference IDs.
Shopify Payments
Shopify admin → Orders → the flagged order → "Chargeback" banner, or Settings → Payments → Manage disputes.
- Order & fulfillment details: Orders → the order → Fulfillment + Timeline (shows when items shipped).
- Tracking number & carrier: Orders → Fulfillment → tracking; confirm "Delivered" status with the carrier.
- Customer info & IP: Order → Customer section; Order → Additional details / fraud analysis for IP and AVS/CVV.
- Fraud analysis (AVS/CVV/risk): Order → "Fraud analysis" panel shows AVS, CVV, and Shopify’s risk indicators.
Square
Square Dashboard → Disputes (or Balance → Disputes), or the email from Square.
- Transaction & receipt: Transactions → the payment → receipt; "Resend receipt" for a copy.
- Card-present / chip details: Transaction detail shows entry method (chip, tap, keyed) — chip reads support card-present disputes.
- Customer details: Customer Directory → the customer; or the transaction’s customer section.
- Itemization & amount: Transaction → itemized breakdown to rebut "incorrect amount" claims.
PayPal
PayPal → Resolution Center → the open case (Dispute, Claim, or Chargeback).
- Transaction details & ID: Activity → the transaction → details; note the Transaction ID.
- Proof of delivery / tracking: Resolution Center → "Respond" → add tracking number + carrier (PayPal validates delivery).
- Proof of shipment / service: Resolution Center evidence upload: invoice, shipment receipt, or service-completion proof.
- Buyer communication: Resolution Center message thread + your own email records with the buyer.
Build a submission-ready Mastercard 4850 response
ChargebackKit assembles your evidence into a formatted, labeled rebuttal pack with the exhibits and response letter card networks expect — pre-mapped to Subscription Cancelled disputes.
Build your evidence pack — $19Or run the free readiness check first.
Frequently asked questions
What is Mastercard reason code 4850?↓
How do I win a 4850?↓
Where does 4850 apply?↓
Where to go next
Build the pack for Subscription Cancelled disputes, or dig into the matching guide, template, and processor evidence requirements.
Build the pack for this dispute
Guides for this dispute
Templates for this dispute
Updated June 2026. This code’s meaning and evidence requirements are sourced from the Mastercard Chargeback Guide and may change as Mastercard revises its rules; always check your processor dashboard for the exact deadline and label on your dispute. The issuer decides every dispute — there is no guaranteed outcome.