MasterCard Do Not Honor Test Card Numbers
MasterCard · Do Not Honor: do_not_honor is a generic issuer decline with no further detail. Many apps map it to a generic card error — test that you do not leak internal codes to end users.
Mastercard test cards use 16-digit BIN ranges distinct from Visa. Use this page when your checkout detects network brand or routes MC-specific decline handling.
When to use: Regression-test generic decline UX and support tooling that buckets unknown declines.
CI tip: Log decline_code from the webhook payload; MockCard mirrors Stripe-shaped error envelopes.
Typical decline_code in webhook payloads: do_not_honor.
Click card to flip
More MasterCard scenarios
Same scenario, other networks
Need webhook race conditions or 3DS abandonment? See payment failure testing and the API docs. Compare plans on pricing.
API example
const res = await fetch("https://mockcard.io/api/v1/generate", {
method: "POST",
headers: {
"Content-Type": "application/json",
"X-Api-Key": process.env.MOCKCARD_API_KEY ?? "",
},
body: JSON.stringify({
brand: "visa", // visa | mastercard | rupay | amex
scenario: "success", // success | insufficient_funds | 3ds_challenge …
}),
});
const card = await res.json();
// { card_number, expiry_month, expiry_year, cvv, brand, scenario }
console.log(card.card_number, card.cvv);