AVS CVV Test Validation Buying Guide
Discover how to validate AVS CVV for secure transactions, understand key features, and avoid common pitfalls.
Redeem your gift cards at any of our Merchants
You can purchase a gift card from any of these locations
Onyx Gift Cards is a Grenadian company designed to introduce, market and manage gift cards systems in Grenada for retailers and corporations. We are enthusiastic about the effect and influence we will have on the local market. We intend to expand our systems regionally with a range of product offerings and services.
Gift cards are the preferred way of giving and receiving gifts. They carry a monetary value that can be redeemed for gifts at your favorite store.
Onyx GiftCards are “Open Gift Cards” which means that they can be redeemed at multiple merchant locations. They are standard credit card size, can fit into the average wallet and made of PVC plastic. Onyx GiftCards are Barcoded for security and safety for the consumer and bear a disclaimer at the back.
Onyx Giftcards can be bought with a branded Card backer which is black in colour and is designed to fit the card. There is an area to write a brief message to the recipient as well.
A CVV and AVS test is a transaction run against a payment gateway sandbox to see how it handles card verification value (CVV) and address verification system (AVS) results. The gateway returns a code for each check, such as match, no match, or not supported. Merchants use those results to set fraud rules before they accept live payments.
Two checks run at the same time when a card is authorized. CVV confirms the card is in hand. AVS confirms the billing address matches issuer records.
AVS compares the numeric parts of the billing address a shopper enters with the address on file at the card issuer. Most systems check the street number and the ZIP code, not the full street name or city. The issuer returns a single letter code that the gateway passes to the merchant.
Codes U, G, and S mean the check never ran. A merchant that blocks every result except Y will turn away valid international shoppers.
Visa, Mastercard, and Discover use a 3 digit code on the back of the card. American Express uses a 4 digit code on the front. The issuer compares the code to its record and returns M, N, P, or U.
PCI DSS rules forbid storing the CVV after authorization. A merchant can pass it to the gateway and keep the result, but never the code itself.
Sandbox transactions never reach the card networks. No money moves, and no issuer sees the request.
Most gateways map these scenarios to specific test card numbers, so you can pick the exact response without guessing.
AVS runs only for cards issued in the US, Canada, and the UK in most cases. Prepaid cards, gift cards, and some digital wallets skip the check. CVV stops a stolen card number from working online, but it does not stop a breach where the code leaks with the number.
A mismatch is a signal, not proof of fraud. Address typos, moves, and shared cards all cause false alarms. Set rules that match your risk level.
No. Running a live card through a test to check CVV or AVS without the cardholder's permission is card fraud and a federal crime in the US. Test card numbers exist so developers can check the same paths without touching anyone's account.
It is a practice charge in a sandbox that shows whether a gateway flags a card security code and billing address as correct.
No. The issuer returns the result and the merchant decides. Many stores decline on a CVV mismatch, while others hold the order for review.
It means the check did not run, often because the bank is outside the AVS region or the data is missing. Treat it as unknown rather than a fail.
Sandbox transactions are free. They never reach the card network, so no authorization or settlement fee applies.
Each gateway and processor publishes its own list, tied to its response codes. Use the list from your provider.