Square Test Card Numbers
Square sandbox test card numbers, plus the CVV, postal code and expiry values that trigger each specific error state.
Square's sandbox accepts 4111 1111 1111 1111 (Visa) with CVV 111 and any future expiry date. American Express uses 3400 000000 00009 with CVV 1111. To force errors, keep a valid card and change one field: CVV 911, postal code 99999 or expiry 01/40.
Last verified against Square's official documentation on .
Successful payments
| Card number | Brand | Result | Copy |
|---|---|---|---|
4111 1111 1111 1111 | Visa | Payment succeeds CVV 111 | |
5105 1051 0510 5100 | Mastercard | Payment succeeds CVV 111 | |
6011 0000 0000 0004 | Discover | Payment succeeds CVV 111 | |
3000 000000 0004 | Diners Club | Payment succeeds CVV 111 | |
3569 9900 1009 5841 | JCB | Payment succeeds CVV 111 | |
3400 000000 00009 | American Express | Payment succeeds CVV 1111 | |
6222 9888 1234 0000 | China UnionPay | Payment succeeds CVV 123 |
Declined cards
| Card number | Brand | Result | Copy |
|---|---|---|---|
4000 0000 0000 0002 | Visa | Card declined | |
4000 0000 0000 0010 | Visa | Card-on-file authentication declined |
Error-state values
Submit a valid test card and change one of these fields to force the matching error.
| Scenario | Value | Effect |
|---|---|---|
| CVV | 911 | Card CVV incorrect |
| Postal code | 99999 | Card postal code incorrect |
| Expiration date | 01/40 | Card expiration date incorrect |
Payment tokens
For testing the API directly without going through the SDKs, use these as source_id.
| Scenario | Value | Effect |
|---|---|---|
| Successful card | cnon:card-nonce-ok | Payment succeeds |
| Declined card | cnon:card-nonce-declined | Payment is declined |
| CVV error | cnon:card-nonce-rejected-cvv | Rejected for CVV mismatch |
Before you use these
- Sandbox only. Set the expiry to any future month and year.
- These numbers are published by Square for sandbox testing. They are not real cards and cannot be used for a real purchase.
How to use Square test cards
- Switch your Square integration to its test or sandbox environment and use test credentials. Live credentials reject these numbers.
- Enter a card number from the tables above. Expiry: Any future month and year. Security code: 111 (1111 for Amex).
- Start with a successful card to confirm the happy path, then work through the decline and error cards so every failure message in your checkout gets exercised.
- Use the trigger values (error-state values, payment tokens) to simulate outcomes that are not tied to a card number.
Square test card FAQ
What are the Square test card numbers?
Square's sandbox accepts 4111 1111 1111 1111 (Visa) with CVV 111 and any future expiry date. American Express uses 3400 000000 00009 with CVV 1111. To force errors, keep a valid card and change one field: CVV 911, postal code 99999 or expiry 01/40.
Do Square test cards work in production?
No. These numbers are only recognised by the Square test environment and are rejected by the live platform. They are not real cards and cannot be used for a purchase.
How do I test a declined payment with Square?
Square triggers failures through error-state values as well as dedicated card numbers. Both are listed on this page.