PayPal lets your customers pay using their PayPal balance, linked bank accounts, or credit and debit cards. It's one of the most recognized payment methods worldwide and can help increase conversion, especially for customers who prefer not to enter card details directly.
What you'll need
To connect PayPal to your CartOS store, you'll need a PayPal Business account. If you currently have a Personal account, you can upgrade it to Business for free in your PayPal settings. Business accounts give you access to the API credentials required for the integration.
Connecting PayPal
In your CartOS admin, go to Settings › Payments. Find PayPal in the list of available payment providers and click Set Up.
You'll be prompted to enter your PayPal API credentials. To find these, log in to your PayPal Business account and navigate to Account Settings › API Access. Under REST API apps, create a new app or use an existing one to get your Client ID and Secret.
Copy the Client ID and Secret into the corresponding fields in CartOS. Select whether you're connecting a Live or Sandbox account—use Sandbox for testing before going live. Click Save to complete the connection.
Enabling PayPal at checkout
Once connected, toggle PayPal to Active in your payment settings. PayPal will now appear as a payment option during checkout.
Customers can click the PayPal button to log in to their PayPal account and complete payment, or use PayPal's guest checkout to pay with a card without creating a PayPal account.
PayPal checkout experience
When a customer selects PayPal, they're redirected to PayPal to authorize the payment. After approval, they return to your store to complete the order. The entire flow happens seamlessly, and order details are captured in your CartOS admin just like any other payment method.
Transaction fees
PayPal charges its own transaction fees, which are separate from any CartOS subscription costs. Fees vary by country and transaction type—check PayPal's current fee schedule for your region. CartOS does not add any additional fees on top of PayPal's charges.
Refunds through PayPal
When you issue a refund in CartOS for a PayPal order, the refund is processed through PayPal automatically. The customer receives the funds back to their original payment method. Partial refunds are supported.
Note that PayPal's transaction fees are typically not refunded when you issue a refund—check PayPal's current policy for details.
Testing with Sandbox
Before accepting live payments, test your integration using PayPal Sandbox. Create sandbox test accounts in your PayPal Developer Dashboard, then connect your Sandbox API credentials in CartOS.
Place test orders using your sandbox buyer account to verify the checkout flow works correctly. Once satisfied, switch to your live credentials to start accepting real payments.
Troubleshooting
If PayPal isn't appearing at checkout, verify that the payment method is toggled to Active and that your API credentials are correct. Invalid credentials will prevent the integration from working.
If customers are seeing errors during checkout, check that your PayPal Business account is in good standing and that there are no restrictions on your account. Currency mismatches can also cause issues—ensure your store currency is supported by your PayPal account.