If you are located in the USA, your bank account needs to meet the following requirements before you connect it to Shopify Payments:
The bank account is a full checking account with a bank in the United States in USD currency.
The bank account is eligible for ACH transfers.
Checking accounts that are set up to accept only wire transfers do not work with Shopify Payments. Savings accounts, flex-currency accounts, virtual accounts, and money-transferring services that mimic bank accounts aren't supported by Shopify Payments.
I thought I'd leave our help guide here on testing the Shopify Payments gateway for your reference. If you're not using Shopify Payments, other payment processors should also have their own test mode too that you can enable. This will allow you to simulate a successful transaction on your store to make sure your checkout is functioning as intended.
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