What is payment gateway testing? Definition and example test cases

Once a customer is ready to purchase, the final frontier lies ahead: the payment process. Because online transactions already come fraught with a learning curve, companies must use extensive payment gateway testing to deliver frictionless payment experiences. Even minor glitches can cause cart abandonment and reduce sales volume. Where other aspects of software may enjoy the leeway to go live while minor problems are ironed out, payment gateways cannot afford anything less than perfect reliability.

Some of the most popular payment gateways are Paypal, Stripe, Amazonpay, and third-party payment processors running on your site. So, what is payments testing, and does it REALLY impact the end-user experience so critically? (Yes… yes, it does.)

What is payment gateway testing?

Payments testing refers to testing the functionality and security of a payment system or application. This can include testing the various components of the system, such as the payment gateway, payment processors, and payment methods, to ensure that they are working correctly and securely. Payment testing can also include testing for compliance with industry regulations and standards and for vulnerabilities and potential security breaches. Payments testing aims to ensure that the payment system is reliable, secure, and compliant while providing an intuitive experience for users.

Payment testing is the thorough testing of every aspect of order transactions, from starting with payment and shipping info to forwarding payment data to merchant accounts to transferring funds to finalizing payment and shipping orders. Payments can fail at any point along this chain due to user and system errors. For example, a payment will fail if a customer enters the wrong expiration date. Similarly, if an API call fails to connect to a financial institution or transaction information is lost between page loads, these things can delay or stop payments entirely.

Failure at any point in the chain can cause frustration and more significant issues. If users can’t remember their 3-digit security code, they may try once or twice and then give up entirely on the sale. If an error comes back that the user can’t understand (e.g., a thrown exception), they’re liable to lose trust. If an order is completed, but payment information can’t validate, companies could find themselves packaging orders without being paid. These are just a few potential impacts to companies and users if payment gateways aren’t thoroughly tested.

Creating a holistic software payments testing strategy

Creating a successful payment gateway testing strategy requires a holistic approach to software testing. Testing payment gateways utilize different software tests against a set of predetermined parameters to check performance and where there’s a need to build out or improve capabilities. Testing must mimic each payment process step to verify that connections and paths for communications are working. You need to test cross-functionality, including test cases like:

• Functional: Confirms that the payment gateway is properly working with the merchant’s system and processing transactions correctly.
• Integration: Check that each new service, payment, or feature added is compatible with the existing app.
• Performance: Verifies the app is performing equally across all devices and O/S combinations and tests for the maximum number of simultaneous transactions from multiple users.
• Usability: Tests the experience of using the payment gateway to ensure it is well-designed and fully functioning.
• Location: Uses region-based testing examples to verify that the payment gateway can handle customer locations and calculate the proper specifications (sales taxes, global shipping fees, import tax).
• Localization: international customers can make payments in their local currency.
• Security: Checks security of PII and financial information. All bank accounts and credit card numbers must be securely transmitted using strong encryption across the transaction.
• Compatibility: Ensures that the payment gateway can manage transactions across different platforms.

See how a top 20 shopping app catches revenue-critical issues and ensures flawless checkouts with Testlio.

Payment gateway testing use cases

Every piece of a payment system needs vetting. These use cases illustrate the complexity of ensuring functional financial transactions across many payment platforms.

• Check card numbers: Make sure credit card numbers can be read, verified, and processed. Create test cases that validate questions like can the payment gateway process credit and debit card information from various financial institutions and countries? 
• Check exchange rates and currency: Ensure foreign purchasers succeed and are charged the right amount. Does the software correctly calculate exchange rates, shipping rates, and local taxes?
• Ensure correct processing time: Check the functionality of the payment gateway when multiple customers are checking out at once. Does processing time change? What happens if the customer’s cart times out?
• Check security measures: Do the card details get masked? Does the customer use 2FA when initiating the transaction? Is your site secure? 
• Confirm successful payment confirmation: Make sure APIs return proper payment confirmation to the customer, financial institution, and your internal software. On the same thread, does payment confirmation trigger auto-pay or auto-renewal?
• Payment failures and following steps: Proper steps should be taken in case of a payment failure, including communication with users and backing orders out of fulfillment systems.