# Reference
Source: https://paymentsandrisk.com/docs/reference

Last updated 24 October 2026.

TL;DR

-   Quick lookups, not learning. Find the code, the threshold or the deadline and get back to work
-   [Decline Codes](https://paymentsandrisk.com/docs/reference/decline-codes/) for why a transaction failed. [Reason Codes](https://paymentsandrisk.com/docs/reference/reason-codes/) for why a chargeback was filed
-   [Time Frames](https://paymentsandrisk.com/docs/reference/time-frames/) for how long you have to respond. Miss that window and you lose automatically
-   Want the concepts instead? Start at [Payments](https://paymentsandrisk.com/docs/payments/), [Chargebacks](https://paymentsandrisk.com/docs/chargebacks/) or [Fraud](https://paymentsandrisk.com/docs/fraud/)

## How to Use This Section

Find what you're after:

| Scenario | Go To |
| --- | --- |
| **Transaction declined, need to know why** | [Decline Codes](https://paymentsandrisk.com/docs/reference/decline-codes/) |
| **Got a chargeback, need the reason code meaning** | [Reason Codes](https://paymentsandrisk.com/docs/reference/reason-codes/) |
| **Need to know how long you have to respond** | [Time Frames](https://paymentsandrisk.com/docs/reference/time-frames/) |
| **Saw an acronym you don't know** | [Acronyms](https://paymentsandrisk.com/docs/reference/acronyms/) or [Glossary](https://paymentsandrisk.com/docs/reference/glossary/) |
| **Want to know if your metrics are normal** | [Benchmarks](https://paymentsandrisk.com/docs/reference/benchmarks/) |
| **ACH payment bounced** | [ACH Return Codes](https://paymentsandrisk.com/docs/reference/return-codes/ach/) |

**Need the why, not the code?** Start here:

-   [Payments](https://paymentsandrisk.com/docs/payments/) - How transactions work
-   [Chargebacks](https://paymentsandrisk.com/docs/chargebacks/) - Dispute process explained
-   [Fraud](https://paymentsandrisk.com/docs/fraud/) - Prevention and detection

* * *

Typical Range Disclaimer

Everything marked "Typical" here assumes US domestic transactions at standard risk. Your numbers will differ. MCC, customer base, transaction mix and geography all move them.

What's Not Covered Yet

This site doesn't yet cover in depth:

-   Marketplace/PayFac operations and compliance
-   Crypto and stablecoin payments
-   Cross-border payout optimization
-   Card program management (issuer-side deep dives)

Might add them later, might not.

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Popular

[❌ Decline Codes Popular Why transactions fail](https://paymentsandrisk.com/docs/reference/decline-codes)

[🔢 Reason Codes Popular Chargeback category lookup](https://paymentsandrisk.com/docs/reference/reason-codes)

[⏰ Time Frames Popular Response deadlines by network](https://paymentsandrisk.com/docs/reference/time-frames)

[📊 Benchmarks Popular What 'good' looks like](https://paymentsandrisk.com/docs/reference/benchmarks)

[📖 Glossary Definitions and terminology](https://paymentsandrisk.com/docs/reference/glossary)

* * *

What You Need Right Now

[❓ "Why was this declined?" Decline codes explain authorization failures](https://paymentsandrisk.com/docs/reference/decline-codes)

[❓ "What's this reason code?" Reason codes explain chargeback categories](https://paymentsandrisk.com/docs/reference/reason-codes)

[❓ "When do I have to respond?" Deadlines by network and stage](https://paymentsandrisk.com/docs/reference/time-frames)

[❓ "What does this mean?" Acronyms: AVS, CVV, ARN, TC40...](https://paymentsandrisk.com/docs/reference/acronyms)

* * *

Card Networks

Card networks make the rules. Which one you're on decides your thresholds and programs.

[🌐 Card Networks Overview Visa, Mastercard, Amex, Discover - who does what and which rules matter](https://paymentsandrisk.com/docs/reference/card-networks)

[💳 Visa VAMP program, 30-day response (see your notice), check your processor's written limit](https://paymentsandrisk.com/docs/reference/card-networks/visa)

[🔴 Mastercard ECM needs 100-299 chargebacks AND a 1.50-2.99% ratio; 45-day response, MATCH list operator](https://paymentsandrisk.com/docs/reference/card-networks/mastercard)

[🔵 American Express Closed-loop, inquiry process, 20-day response, premium cardholders](https://paymentsandrisk.com/docs/reference/card-networks/amex)

[🟠 Discover Smallest network, no published threshold or response window. Get your deadline from your acquirer in writing](https://paymentsandrisk.com/docs/reference/card-networks/discover)

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Reason Codes by Network

Every chargeback has a code. The code tells you why. It also tells you what evidence you'll need to fight it.

[💳 Visa 10.4 (fraud), 13.1 (not received), 13.2 (cancelled recurring)](https://paymentsandrisk.com/docs/reference/reason-codes/visa)

[🔴 Mastercard 4837 (fraud), 4853 (dispute), 4834 (POI error)](https://paymentsandrisk.com/docs/reference/reason-codes/mastercard)

[🔵 Amex F29 (fraud), C08 (goods not received), C28 (cancelled recurring)](https://paymentsandrisk.com/docs/reference/reason-codes/amex)

[🟠 Discover UA02 (fraud), RG (not received), AP (recurring)](https://paymentsandrisk.com/docs/reference/reason-codes/discover)

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Decline Codes

[Decline Codes](https://paymentsandrisk.com/docs/reference/decline-codes/) - why an authorization failed, and what you can do about it.

The ones you'll see constantly:

-   **05** (Do Not Honor) - the issuer's shrug. A retry sometimes works
-   **51** (Insufficient Funds) - there's no money there
-   **14** (Invalid Card Number) - a typo, or a test card
-   **54** (Expired Card) - you'll need a fresh card on file

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ACH Return Codes

[ACH Return Codes](https://paymentsandrisk.com/docs/reference/return-codes/ach/) - why ACH payments bounce.

The ones that matter:

-   **R01** (Insufficient Funds) - the common one. You can retry
-   **R10** (Unauthorized consumer debit) - use the [ACH debit return rules](https://paymentsandrisk.com/docs/payments/payment-methods/bank-transfers/#return-timeframes)
-   **R29** (Corporate Unauthorized) - R10's corporate twin

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Response Deadlines

[Time Frames](https://paymentsandrisk.com/docs/reference/time-frames/) - miss one and you've lost automatically.

| Network | Representment | Pre-Arb | Arbitration |
| --- | --- | --- | --- |
| Visa | 30 days (see your notice) | 30 days | 45 days |
| Mastercard | 45 days | 30 days | 45 days |
| Amex | 20 days | No such stage | No such stage |
| Discover | Not published | Not published | Exists, window not published |

Discover doesn't publish its dispute windows. Get them from your acquirer in writing, and work to the date on your notice.

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Terminology

[📖 Glossary Definitions and terminology](https://paymentsandrisk.com/docs/reference/glossary)

[🔤 Acronyms AVS, CVV, ARN, TC40, etc.](https://paymentsandrisk.com/docs/reference/acronyms)

[🔍 Fraud Classification Identify fraud types and responses](https://paymentsandrisk.com/docs/reference/fraud-classification)

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## Next Steps

Looking up a code?

1.  [Decline Codes](https://paymentsandrisk.com/docs/reference/decline-codes) - Auth failures
2.  [Reason Codes](https://paymentsandrisk.com/docs/reference/reason-codes) - Chargeback categories
3.  [ACH Return Codes](https://paymentsandrisk.com/docs/reference/return-codes/ach) - Bank returns

Need context?

1.  [Payments Overview](https://paymentsandrisk.com/docs/payments) - How transactions work
2.  [Chargebacks Overview](https://paymentsandrisk.com/docs/chargebacks) - Dispute process
3.  [Fraud Types](https://paymentsandrisk.com/docs/fraud/types) - Threat landscape

Building a process?

1.  [Benchmarks](https://paymentsandrisk.com/docs/reference/benchmarks) - What "good" looks like
2.  [Time Frames](https://paymentsandrisk.com/docs/reference/time-frames) - Critical deadlines
3.  [Experimentation](https://paymentsandrisk.com/docs/reference/experimentation) - Test safely

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## See Also

[💳 Payments](https://paymentsandrisk.com/docs/payments)[💰 Chargebacks](https://paymentsandrisk.com/docs/chargebacks)[🔍 Fraud Types](https://paymentsandrisk.com/docs/fraud/types)[📋 Compliance](https://paymentsandrisk.com/docs/compliance)

-   [Fraud Prevention](https://paymentsandrisk.com/docs/fraud/prevention/) - Stopping fraud
-   [Operations](https://paymentsandrisk.com/docs/operations/) - Operational processes
-   [Playbooks](https://paymentsandrisk.com/docs/playbooks/) - Step-by-step guides
-   [Network Programs](https://paymentsandrisk.com/docs/chargebacks/reference/network-programs/) - VAMP, ECM thresholds
-   [3D Secure](https://paymentsandrisk.com/docs/fraud/prevention/3ds/) - Authentication
-   [AVS & CVV](https://paymentsandrisk.com/docs/fraud/prevention/avs-cvv/) - Verification signals
-   [Chargeback Metrics](https://paymentsandrisk.com/docs/chargebacks/metrics/) - Tracking disputes
-   [Fraud Metrics](https://paymentsandrisk.com/docs/fraud/metrics/) - Measuring performance