How to Connect Mollie to Odoo: European Payment Gateway Integration

Why Mollie for Odoo in Europe?

European payment preferences vary dramatically by country. Dutch customers expect iDEAL. Belgian customers use Bancontact. German customers prefer Sofort or Giropay. French customers use Carte Bancaire. Mollie supports all of these through a single integration, plus standard credit cards, SEPA Direct Debit, Apple Pay, and more. For European businesses running Odoo, Mollie provides the broadest coverage of local payment methods with the simplest integration.

Supported Payment Methods

Prerequisites

• Odoo 17 or 18 with Payment Provider and optionally eCommerce modules
• Mollie account (sign up at mollie.com — no monthly fees, pay per transaction)
• Mollie API key (live and test)
• European business entity

Step 1: Get Mollie API Keys

1. Log into mollie.com/dashboard
2. Go to Developers → API Keys
3. Copy your Live API Key (starts with live_)
4. Copy your Test API Key (starts with test_)
5. Complete your account verification (business documents, bank account)

Step 2: Install the Mollie Module

Odoo includes a native Mollie payment provider in version 17 and later:

1. Go to Apps in Odoo
2. Search for Mollie (technical name: payment_mollie)
3. Install the module

Step 3: Configure the Payment Provider

1. Go to Invoicing/Accounting → Configuration → Payment Providers
2. Click on Mollie
3. Enter your API Key
4. Set state to Test Mode
5. In the Configuration tab, select which payment methods to enable
6. Click Save

Step 4: Configure Payment Methods

Mollie auto-detects which payment methods are available based on your account and the customer's country:

1. In the Mollie payment provider settings, go to Payment Methods
2. Enable the methods relevant to your customer base
3. Set minimum and maximum amounts if needed (some methods have limits)
4. Configure icons to display during checkout

Tip: Enable all relevant methods and let Mollie handle the display logic. It will only show payment methods available in the customer's country.

Step 5: Test Payments

1. With test mode active, create a sale order and send a payment link
2. Or go through your Odoo eCommerce checkout
3. Mollie's test mode shows a simulated payment screen
4. Select the payment status to simulate (paid, failed, cancelled, expired)
5. Verify the result appears correctly in Odoo

Step 6: Go Live

1. Switch the Mollie provider state to Enabled
2. Replace the test API key with the live API key
3. Make a small real transaction to verify end-to-end flow
4. Check Odoo Accounting for the payment reconciliation

Step 7: Configure Webhooks

Mollie uses webhooks to notify Odoo of payment status changes:

• Odoo automatically registers the webhook URL when you configure the provider
• The URL follows the pattern: https://your-odoo.com/payment/mollie/webhook
• Ensure this URL is accessible from the internet (not behind VPN or IP whitelist)
• Mollie retries failed webhooks for up to 12 hours

SEPA Direct Debit for Recurring Payments

For subscription or recurring invoice payments:

1. Enable SEPA Direct Debit in your Mollie Dashboard
2. Customers provide a mandate during first payment
3. Subsequent charges are pulled from their bank account automatically
4. SEPA mandates are stored securely by Mollie
5. In Odoo, link the mandate to the customer's payment token

Troubleshooting

Payment Page Shows No Methods

Mollie filters methods by country, currency, and amount. If the payment amount is below the minimum for a method (e.g., iDEAL minimum is usually 0.01 EUR), it will not appear. Check that your Odoo currency matches the payment method's supported currencies.

Webhook Errors

If payments succeed in Mollie but Odoo does not update, the webhook is failing. Check Odoo's log for errors on the /payment/mollie/webhook endpoint. Common causes: Odoo URL not publicly accessible, SSL certificate issues, or Odoo throwing an exception during payment processing.

Refund Not Appearing in Mollie

Process refunds through Odoo's credit note workflow. The Mollie module sends the refund request to Mollie's API. If it fails, check that the original payment is in a refundable state (captured, not just authorized) and that your Mollie account balance covers the refund.

DeployMonkey Mollie Setup

DeployMonkey instances come with HTTPS and public URLs configured, so Mollie webhooks work immediately. Our AI agent can help configure payment methods for your target European markets and troubleshoot any integration issues.