Checkout with WooCommerce Payments

This tutorial was written by Claude Code (an AI) and has not yet been reviewed. Follow along with caution. If the tutorial was helpful or a specific part was not clear/correct, please provide feedback at the bottom of the page. Thank you.

This guide covers integrating WooPay (WooCommerce Payments) with CoCart Preview API. Requires CoCart v4.6+ and WooCommerce Payments configured with WooPay enabled.

Overview

WooPay is the express checkout feature of WooCommerce Payments, which is built on Stripe’s infrastructure. This means you can use the Stripe SDK directly with your WooCommerce Payments account for headless checkout implementations.

This tutorial is specifically for WooCommerce Payments users. If you’re using the standalone WooCommerce Stripe Gateway plugin, see the Stripe tutorial instead. Both use Stripe’s infrastructure, but require different payment method IDs.Key Differences:

WooCommerce Payments: Available in 39 countries, managed by WooCommerce/Automattic, includes WooPay express checkout. (payment_method: 'woocommerce_payments')
Stripe Gateway: Available in 45+ countries, direct Stripe integration, full control over Stripe account. (payment_method: 'stripe')

View supported countries

Why This Works

WooCommerce Payments operates on Stripe’s payment processing infrastructure:

Your WooCommerce Payments account is a Stripe Connect account
You can use Stripe.js v3 for client-side payment processing
All Stripe SDK features are available to you
Your publishable key starts with pk_test_ or pk_live_

Prerequisites

Before implementing WooPay checkout, ensure you have:

Supported country - Your business must be registered in one of the supported countries
WooCommerce Payments plugin installed and configured
WooPay enabled in WooCommerce Payments settings
A valid cart with items added via CoCart API
Customer billing address information
Stripe.js v3 loaded in your frontend

Integration Flow

Get Your Stripe Credentials

Extract your Stripe publishable key from WooCommerce Payments

Initialize Stripe SDK

Set up Stripe.js with your WooCommerce Payments credentials

Create Payment Elements

Build the payment form using Stripe Elements

Collect Payment Details

Let customers securely enter payment information

Complete Checkout

Submit checkout with payment data to CoCart

Step 1: Get Your Stripe Credentials

Since WooCommerce Payments runs on Stripe, you need to extract your Stripe publishable key. Choose one of these methods:

Method A: Admin Notice Helper (Recommended)

Add this temporary code to your functions.php or custom plugin:

/**
 * Display WooCommerce Payments Stripe Keys
 * For development purposes only - remove after use
 */
add_action('admin_notices', function() {
    if (!current_user_can('manage_woocommerce')) {
        return;
    }

    if (!class_exists('WC_Payments')) {
        return;
    }

    $account_service = WC_Payments::get_account_service();
    if (!$account_service) {
        return;
    }

    $is_test_mode = WC_Payments::mode()->is_test();
    $publishable_key = $account_service->get_publishable_key($is_test_mode);
    $account_id = $account_service->get_stripe_account_id();

    if ($publishable_key) {
        echo '<div class="notice notice-info is-dismissible">';
        echo '<h3>WooCommerce Payments - Stripe Credentials</h3>';
        echo '<p><strong>Mode:</strong> ' . ($is_test_mode ? 'Test Mode' : 'Live Mode') . '</p>';
        echo '<p><strong>Publishable Key:</strong> <code style="user-select: all;">' . esc_html($publishable_key) . '</code></p>';
        echo '<p><strong>Stripe Account ID:</strong> <code style="user-select: all;">' . esc_html($account_id) . '</code></p>';
        echo '<p><em>⚠️ Remove this code snippet after copying your keys!</em></p>';
        echo '</div>';
    }
});

Steps:

Add the code above to your site temporarily
Navigate to WordPress Admin Dashboard
Look for the “WooCommerce Payments - Stripe Credentials” notice
Copy your Publishable Key (starts with pk_test_ or pk_live_)
Important: Remove the helper code after copying

Method B: Browser Console (Simpler)

Go to your WooCommerce checkout page
Press F12 to open Developer Tools
Go to the Console tab
Run this command:

// Copy publishable key to clipboard
copy(wcpay_upe_config.publishableKey);
console.log('✓ Publishable key copied to clipboard!');
console.log('Account ID:', wcpay_upe_config.accountId);
console.log('Test Mode:', wcpay_upe_config.testMode);

Security Reminders:

✅ Publishable keys are safe to expose client-side (that’s their purpose)
⚠️ NEVER expose secret/private keys
🔒 Always use test mode keys during development (pk_test_)
🗑️ Remove helper code after obtaining keys

Step 2: Load Stripe SDK

Add Stripe.js to your frontend application:

<!-- Load Stripe.js v3 -->
<script src="https://js.stripe.com/v3/"></script>

Or via npm/yarn if using a build system:

npm install @stripe/stripe-js
# or
yarn add @stripe/stripe-js

import { loadStripe } from '@stripe/stripe-js';

Step 3: Initialize Stripe Elements

Set up Stripe with your WooCommerce Payments publishable key:

Vanilla JavaScript
React
HTML Form

// Initialize Stripe with WooCommerce Payments key
const stripe = Stripe('pk_test_XXXXXXXXXXXXX'); // Your WCPay publishable key
const elements = stripe.elements();

// Create card element with custom styling
const cardElement = elements.create('card', {
    style: {
        base: {
            fontSize: '16px',
            color: '#32325d',
            fontFamily: '-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif',
            '::placeholder': {
                color: '#aab7c4',
            },
        },
        invalid: {
            color: '#fa755a',
            iconColor: '#fa755a'
        },
    },
    hidePostalCode: false,
});

// Mount the card element
cardElement.mount('#card-element');

// Handle real-time validation
cardElement.on('change', ({error}) => {
    const displayError = document.getElementById('card-errors');
    if (error) {
        displayError.textContent = error.message;
        displayError.style.display = 'block';
    } else {
        displayError.textContent = '';
        displayError.style.display = 'none';
    }
});

Step 4: Create Payment Method

When the customer submits the form, create a payment method using Stripe:

async function handlePaymentSubmission(event) {
    event.preventDefault();

    const form = event.target;
    const submitButton = form.querySelector('#submit-button');

    // Disable submit button
    submitButton.disabled = true;
    submitButton.textContent = 'Processing...';

    try {
        // Collect billing data from form
        const billingData = {
            first_name: form.billing_first_name.value,
            last_name: form.billing_last_name.value,
            email: form.billing_email.value,
            phone: form.billing_phone?.value || '',
            address_1: form.billing_address_1.value,
            city: form.billing_city.value,
            state: form.billing_state.value,
            postcode: form.billing_postcode.value,
            country: form.billing_country.value
        };

        // Create payment method with Stripe
        const {paymentMethod, error} = await stripe.createPaymentMethod({
            type: 'card',
            card: cardElement,
            billing_details: {
                name: `${billingData.first_name} ${billingData.last_name}`,
                email: billingData.email,
                phone: billingData.phone,
                address: {
                    line1: billingData.address_1,
                    city: billingData.city,
                    state: billingData.state,
                    postal_code: billingData.postcode,
                    country: billingData.country,
                }
            },
        });

        if (error) {
            throw new Error(error.message);
        }

        console.log('Payment method created:', paymentMethod.id);

        // Proceed to checkout
        await processCheckout(billingData, paymentMethod);

    } catch (error) {
        console.error('Payment failed:', error);
        document.getElementById('card-errors').textContent = error.message;

        // Re-enable submit button
        submitButton.disabled = false;
        submitButton.textContent = 'Complete Order';
    }
}

// Attach to form
document.getElementById('payment-form').addEventListener('submit', handlePaymentSubmission);

Step 5: Complete Checkout

Process the checkout with CoCart using the payment method:

async function processCheckout(billingAddress, paymentMethod) {
    const cartKey = localStorage.getItem('cart_key');

    try {
        const response = await fetch('https://your-store.com/wp-json/cocart/preview/checkout', {
            method: 'PUT',
            headers: {
                'Cart-Key': cartKey,
                'Content-Type': 'application/json',
            },
            body: JSON.stringify({
                billing_address: billingAddress,
                payment_method: 'woocommerce_payments', // Important: use WooCommerce Payments ID
                payment_method_data: {
                    payment_method: paymentMethod.id // Stripe payment method ID
                }
            })
        });

        const result = await response.json();

        if (!response.ok) {
            throw new Error(result.message || 'Checkout failed');
        }

        // Handle successful order
        if (result.order_id) {
            console.log('Order created successfully:', result.order_id);

            // Clear cart
            localStorage.removeItem('cart_key');

            // Show success message
            showSuccessMessage(`Order #${result.order_number} completed!`);

            // Redirect to thank you page
            if (result.payment_result?.redirect_url) {
                setTimeout(() => {
                    window.location.href = result.payment_result.redirect_url;
                }, 2000);
            }
        }

    } catch (error) {
        console.error('Checkout error:', error);
        throw error;
    }
}

function showSuccessMessage(message) {
    const errorElement = document.getElementById('card-errors');
    errorElement.textContent = message;
    errorElement.style.color = '#28a745';
    errorElement.style.display = 'block';
}

Complete Integration Example

Here’s a complete, production-ready implementation:

class WooPayCheckout {
    constructor(publishableKey) {
        this.stripe = null;
        this.cardElement = null;
        this.publishableKey = publishableKey;
    }

    async initialize() {
        try {
            // Initialize Stripe
            this.stripe = Stripe(this.publishableKey);

            // Create Elements
            const elements = this.stripe.elements();

            // Create and mount card element
            this.cardElement = elements.create('card', {
                style: {
                    base: {
                        fontSize: '16px',
                        color: '#32325d',
                        fontFamily: 'system-ui, sans-serif',
                        '::placeholder': {
                            color: '#aab7c4',
                        },
                    },
                    invalid: {
                        color: '#fa755a',
                        iconColor: '#fa755a',
                    },
                },
                hidePostalCode: false,
            });

            this.cardElement.mount('#card-element');

            // Setup validation
            this.setupValidation();

            // Setup form submission
            this.setupFormSubmission();

            console.log('WooPay checkout initialized');
        } catch (error) {
            console.error('WooPay initialization error:', error);
            this.showError('Payment system unavailable. Please refresh and try again.');
        }
    }

    setupValidation() {
        this.cardElement.on('change', ({error}) => {
            const errorElement = document.getElementById('card-errors');
            if (error) {
                errorElement.textContent = error.message;
                errorElement.style.display = 'block';
            } else {
                errorElement.textContent = '';
                errorElement.style.display = 'none';
            }
        });
    }

    setupFormSubmission() {
        const form = document.getElementById('payment-form');

        form.addEventListener('submit', async (event) => {
            event.preventDefault();
            await this.handleSubmit(form);
        });
    }

    async handleSubmit(form) {
        const submitButton = form.querySelector('#submit-button');
        const originalText = submitButton.textContent;

        try {
            // Disable submit button
            submitButton.disabled = true;
            submitButton.textContent = 'Processing Payment...';

            // Get billing address
            const billingAddress = this.getBillingAddressFromForm(form);

            // Create payment method
            const {paymentMethod, error} = await this.stripe.createPaymentMethod({
                type: 'card',
                card: this.cardElement,
                billing_details: {
                    name: `${billingAddress.first_name} ${billingAddress.last_name}`,
                    email: billingAddress.email,
                    phone: billingAddress.phone,
                    address: {
                        line1: billingAddress.address_1,
                        city: billingAddress.city,
                        state: billingAddress.state,
                        postal_code: billingAddress.postcode,
                        country: billingAddress.country,
                    }
                },
            });

            if (error) {
                throw new Error(error.message);
            }

            // Process checkout
            await this.processCheckout(billingAddress, paymentMethod);

        } catch (error) {
            console.error('Payment error:', error);
            this.showError(error.message || 'Payment failed. Please try again.');
        } finally {
            submitButton.disabled = false;
            submitButton.textContent = originalText;
        }
    }

    getBillingAddressFromForm(form) {
        const formData = new FormData(form);
        return {
            first_name: formData.get('billing_first_name'),
            last_name: formData.get('billing_last_name'),
            email: formData.get('billing_email'),
            phone: formData.get('billing_phone') || '',
            address_1: formData.get('billing_address_1'),
            city: formData.get('billing_city'),
            state: formData.get('billing_state'),
            postcode: formData.get('billing_postcode'),
            country: formData.get('billing_country')
        };
    }

    async processCheckout(billingAddress, paymentMethod) {
        const cartKey = localStorage.getItem('cart_key');

        const response = await fetch('/wp-json/cocart/preview/checkout', {
            method: 'PUT',
            headers: {
                'Cart-Key': cartKey,
                'Content-Type': 'application/json',
            },
            body: JSON.stringify({
                billing_address: billingAddress,
                payment_method: 'woocommerce_payments',
                payment_method_data: {
                    payment_method: paymentMethod.id
                }
            })
        });

        const result = await response.json();

        if (!response.ok) {
            throw new Error(result.message || `Checkout failed (${response.status})`);
        }

        // Handle success
        this.handleCheckoutSuccess(result);

        return result;
    }

    handleCheckoutSuccess(result) {
        this.showSuccess(`Order #${result.order_number} completed successfully!`);

        // Clear cart
        localStorage.removeItem('cart_key');

        // Redirect to thank you page
        if (result.payment_result?.redirect_url) {
            setTimeout(() => {
                window.location.href = result.payment_result.redirect_url;
            }, 2000);
        }
    }

    showError(message) {
        const errorElement = document.getElementById('card-errors');
        errorElement.textContent = message;
        errorElement.style.color = '#fa755a';
        errorElement.style.display = 'block';
    }

    showSuccess(message) {
        const errorElement = document.getElementById('card-errors');
        errorElement.textContent = message;
        errorElement.style.color = '#28a745';
        errorElement.style.display = 'block';
    }
}

// Initialize when DOM is ready
document.addEventListener('DOMContentLoaded', async () => {
    // Replace with your actual WooCommerce Payments publishable key
    const publishableKey = 'pk_test_XXXXXXXXXXXXX';

    const checkout = new WooPayCheckout(publishableKey);
    await checkout.initialize();
});

Error Handling

Handle common WooPay/Stripe errors gracefully:

function handlePaymentError(error) {
    let userMessage = 'Payment failed. Please try again.';

    // Map error codes to user-friendly messages
    const errorMessages = {
        'card_declined': 'Your card was declined. Please try a different payment method.',
        'insufficient_funds': 'Insufficient funds. Please use a different card.',
        'expired_card': 'Your card has expired. Please use a different card.',
        'incorrect_cvc': 'The security code is incorrect. Please check and try again.',
        'incorrect_number': 'The card number is incorrect. Please check and try again.',
        'processing_error': 'An error occurred while processing your card. Please try again.',
        'rate_limit': 'Too many requests. Please wait a moment and try again.',
    };

    if (error.code && errorMessages[error.code]) {
        userMessage = errorMessages[error.code];
    } else if (error.message) {
        userMessage = error.message;
    }

    // Display error to user
    const errorElement = document.getElementById('card-errors');
    errorElement.textContent = userMessage;
    errorElement.style.display = 'block';

    // Log for debugging
    console.error('Payment error details:', {
        code: error.code,
        message: error.message,
        type: error.type
    });
}

Testing

Test Card Numbers

Use Stripe’s test cards in test mode:

Card Number	Scenario
`4242424242424242`	Successful payment
`4000000000000002`	Card declined
`4000000000009995`	Insufficient funds
`4000000000000069`	Expired card
`4000000000000127`	Incorrect CVC

Test Details

CVC: Any 3-digit number (4 digits for Amex)
Expiry: Any future date
Postal Code: Any valid postal code

Enable Test Mode

Ensure WooCommerce Payments is in test mode:

Go to WooCommerce → Settings → Payments
Click WooCommerce Payments
Check “Enable test mode”
Save changes

WooPay Express Checkout

WooPay also offers express checkout features. To check if WooPay express is enabled:

// Available on checkout pages
if (wcpay_upe_config.isWooPayExpressCheckoutEnabled) {
    console.log('WooPay Express is enabled');
    console.log('WooPay Host:', wcpay_upe_config.woopayHost);
}

WooPay Express Checkout integration is beyond the scope of this tutorial. This guide focuses on standard credit card processing using WooCommerce Payments’ Stripe infrastructure.

Best Practices

Security

Never expose secret keys client-side
Always use HTTPS in production
Validate billing data before submission
Use test mode for development
Remove helper code from production

User Experience

Show loading states during processing
Provide clear, specific error messages
Enable real-time card validation
Support mobile-friendly inputs
Display accepted card types

Error Handling

Handle network failures gracefully
Log errors for debugging
Provide retry mechanisms
Never expose technical details to users
Test all error scenarios

Performance

Load Stripe.js asynchronously
Minimize unnecessary API calls
Implement request timeouts
Cache publishable keys appropriately
Monitor payment processing times

Troubleshooting

Common Issues

WooCommerce Payments Not Available in My Country

Problem: Cannot install or activate WooCommerce Payments in your country.Solution: WooCommerce Payments is available in 39 countries. If your country is not on this list, use WooCommerce Stripe Gateway instead.WooCommerce Payments Supported Countries (39): Australia, Austria, Belgium, Bulgaria, Canada, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hong Kong, Hungary, Ireland, Italy, Japan, Latvia, Lithuania, Luxembourg, Malta, Netherlands, New Zealand, Norway, Poland, Portugal, Romania, Singapore, Slovakia, Slovenia, Spain, Sweden, Switzerland, UAE, United Kingdom, United StatesIf your country is NOT listed above:Option 1: Use WooCommerce Stripe Gateway (Recommended)

Uninstall WooCommerce Payments (if installed)
Install WooCommerce Stripe Gateway plugin
Create a direct Stripe account at stripe.com
Follow the Stripe tutorial instead
Use payment_method: 'stripe' in your checkout code

Why Stripe Gateway for unsupported countries?

Available in 45+ countries (more than WooCommerce Payments)
Includes additional countries like Brazil, India, Indonesia, Malaysia, Mexico, Thailand
Direct control over your Stripe account
Same Stripe infrastructure and security
Full API access for headless commerce

Important Notes:

Your business registration location determines eligibility, not your personal residence
UAE only supports Business accounts (not Individual accounts)
Check if your country supports WooCommerce Payments
Check if your country supports Stripe directly

'Stripe is not defined' Error

Problem: Stripe.js hasn’t loaded before initialization.Solution: Wait for the script to load:

function loadStripe() {
    return new Promise((resolve) => {
        if (typeof Stripe !== 'undefined') {
            resolve(Stripe);
            return;
        }

        const script = document.createElement('script');
        script.src = 'https://js.stripe.com/v3/';
        script.onload = () => resolve(Stripe);
        document.head.appendChild(script);
    });
}

// Usage
const Stripe = await loadStripe();
const stripe = Stripe('pk_test_xxx');

Payment Method Not Accepted

Problem: Backend doesn’t recognize payment method.Solution: Ensure you’re using the correct payment method ID:

Use 'woocommerce_payments' (not 'stripe')
Verify WooCommerce Payments is enabled and active
Check that WooCommerce Payments is configured in test/live mode appropriately
Important: If your country is not in the 39 supported countries, WooCommerce Payments won’t work - use Stripe Gateway instead

Card Element Not Displaying

Problem: Card input field doesn’t appear.Solution: Verify the following:

Element ID matches: cardElement.mount('#card-element')
Container exists in DOM before mount
No CSS conflicts hiding the element
Check browser console for errors

Publishable Key Not Found

Problem: Can’t retrieve WooCommerce Payments credentials.Solution:

Ensure WooCommerce Payments is fully set up and connected
Verify you’re on a checkout page when using browser console method
Check that WooCommerce Payments is activated (not just installed)
Try the admin notice helper method instead

Additional Resources

WooCommerce Payments Documentation
Stripe Elements Documentation
Stripe API Reference
CoCart Checkout API Reference
Payment Processing Fundamentals
Stripe Gateway Tutorial - For standalone Stripe plugin users

Always thoroughly test your WooPay integration in test mode before enabling live payments. Verify that webhooks are configured and orders are being created correctly in WooCommerce.

Remember: WooCommerce Payments uses Stripe’s infrastructure, so all Stripe documentation and best practices apply to your implementation. The key difference is using payment_method: 'woocommerce_payments' when submitting to CoCart’s Checkout API.

Tutorials

Checkout API

Framework Integrations

Tips and Tricks

Resources

Checkout with WooCommerce Payments

Overview

Why This Works

Prerequisites

Integration Flow

Step 1: Get Your Stripe Credentials

Method A: Admin Notice Helper (Recommended)

Method B: Browser Console (Simpler)

Step 2: Load Stripe SDK

Step 3: Initialize Stripe Elements

Step 4: Create Payment Method

Step 5: Complete Checkout

Complete Integration Example

Error Handling

Testing

Test Card Numbers

Test Details

Enable Test Mode

WooPay Express Checkout

Best Practices

Security

User Experience

Error Handling

Performance

Troubleshooting

Common Issues

Additional Resources

Tutorials

Checkout API

Framework Integrations

Tips and Tricks

Resources

​Overview

​Why This Works

​Prerequisites

​Integration Flow

​Step 1: Get Your Stripe Credentials

​Method A: Admin Notice Helper (Recommended)

​Method B: Browser Console (Simpler)

​Step 2: Load Stripe SDK

​Step 3: Initialize Stripe Elements

​Step 4: Create Payment Method

​Step 5: Complete Checkout

​Complete Integration Example

​Error Handling

​Testing

​Test Card Numbers

​Test Details

​Enable Test Mode

​WooPay Express Checkout

​Best Practices

Security

User Experience

Error Handling

Performance

​Troubleshooting

​Common Issues

​Additional Resources

Overview

Why This Works

Prerequisites

Integration Flow

Step 1: Get Your Stripe Credentials

Method A: Admin Notice Helper (Recommended)

Method B: Browser Console (Simpler)

Step 2: Load Stripe SDK

Step 3: Initialize Stripe Elements

Step 4: Create Payment Method

Step 5: Complete Checkout

Complete Integration Example

Error Handling

Testing

Test Card Numbers

Test Details

Enable Test Mode

WooPay Express Checkout

Best Practices

Troubleshooting

Common Issues

Additional Resources