Do not work from a static code table
Visa, Mastercard and other schemes maintain their own dispute categories and rules. Acquirers may display those codes through different portal labels. For an active case, use the code, description and deadline in the current notice and open the provider’s linked guidance.
A website list can explain broad themes, but it should not replace the live case instructions.
Translate the code into one question
Fraud or no authorisation
What connects the cardholder or authorised user to this transaction under the applicable rules?
Processing error
What records show the amount, currency, timing and number of valid transactions?
Consumer dispute
What was promised, accepted, delivered, cancelled or refunded?
Timing or presentation
What do the authorisation, clearing, delivery and submission dates show?
Match exhibits to the allegation
Name and number each exhibit. Use a one-page chronology to point from the allegation to the order record, terms accepted, customer communications and fulfilment evidence. A large unstructured export makes the reviewer find the argument for you.
Never invent a universal deadline or win rate
Response windows can differ by scheme stage, provider and case. Success depends on the facts and the evidence. Record the exact portal deadline and submit early enough to resolve rejected files or missing documents.
Use outcomes to reduce recurrence
- Fix confusing billing descriptors.
- Make cancellation and refund status visible.
- Capture delivery or service-completion evidence.
- Investigate repeated products, channels, staff actions or fraud signals.
- Review authentication and fraud rules with the gateway or acquirer.
How to structure a UK chargeback representment
A repeatable format that wins meaningfully more disputes than ad-hoc responses.
- 1
Read the reason code
Do not respond generically. Identify what the issuer is actually claiming; your evidence must rebut that specific claim.
- 2
Draft a one-page cover letter
State the transaction, the reason code, and your counter-argument in three short paragraphs. Reference numbered evidence pieces.
- 3
Assemble evidence in order
Order confirmation, delivery proof, authentication data, T&Cs excerpt, communication log. One clean PDF, no duplicates.
- 4
Include hard authentication data
For CNP, the 3DS2 ECI, CAVV and AVS values are the single most persuasive evidence. Pull them from your gateway.
- 5
Submit before the deadline
Late representments are auto-lost. Diary the deadline; most schemes give 20 days from the chargeback.
- 6
Track outcomes and iterate
Log every dispute by reason code, product line and channel. Attack the top-two reason codes every quarter.
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About this guide
Published by Card Payment Connect, an independent card-payment consultancy for UK businesses. Reviewed by Matthew McCarthy, who has worked in UK merchant services for over a decade. Last reviewed 11 September 2026.