Your customer pays the first order with iDEAL or Bancontact. That payment gives us their bank account, and every following order is collected from it by direct debit. Five steps, about ten minutes.
Do this first, because Mollie reviews it by hand and that takes up to three business days. In your Mollie Dashboard, click your organisation name in the top left, go to Settings → Payment methods and activate SEPA Direct Debit (Mollie explains it here).
Have your subscription plans live on a product page before you ask, because Mollie looks at your website. Without this, first payments work and renewals never happen.
In the app: Settings → Integrations → Mollie → Configure.

Click Connect with Mollie, sign in to Mollie and approve. Only you can do this, because it happens inside your own Mollie account. No account yet? Create a Mollie account starts the sign-up and brings you back here. You do this once.

Pick your Mollie profile, tick Test mode if you are still testing, and click Save. The other two fields are fine as they are.

Shopify hides iDEAL and Bancontact as soon as a cart holds a subscription, so the app adds its own button. Below the connection, tick Show the Mollie checkout button, open Payment methods and tick what you accept, then save. Cards cannot start this kind of subscription, so they stay greyed out.

Below it sits a second, optional button: Card checkout button. It leads to your regular Shopify checkout with the subscription kept, where Shopify offers cards, PayPal and wallets and bills the subscription itself. Buyers were seeing "Checkout" next to "Pay with iDEAL" with nothing saying the first one meant paying by card, and this labels it. You choose the wording, which of Shopify's own payment icons ride on it, and which of the two buttons comes first.
Show only the methods your regular checkout really offers. The icons are a promise to your customer, and Apple Pay and Shop Pay appear only on the devices that support them.
One last click: the button only appears once the app embed is on in your theme. The card says so and its Enable in theme editor link opens the editor with everything already switched on, so you only press Save.


Mollie has not released your methods yet. The banner names each one and what it is waiting for.
SEPA Direct Debit is still off, see Step 1.
Mollie approved something after you saved? Come back here and press Save again, so the button picks it up.
Try it yourself first: Test a subscription before going live.
See what happens each month in How Mollie subscriptions renew with SEPA Direct Debit.
Stuck on any of this? Open the chat in the bottom right corner of the app and we will help you set it up.