An add-on is a one-time extra sold alongside a subscription. It never repeats: it rides along with one order and disappears. Add-ons are configured per plan, in two separate places.
Add-ons need a paid plan, Growth or higher. On the Free plan the card is read-only and existing settings are untouched.
Go to Plans, open a plan and scroll to the Add-on products card. The card is split by a Storefront badge and a Customer account badge, because the two work differently.
Under Featured add-on (product page), the section Optional add-on at checkout holds a single product. Click Select product, then tick Show on product page, choose the Variant, and optionally set a Discount type (Percentage or Fixed amount) and Discount value.
Not sure what to pair? Suggest with AI reads the products on the plan and proposes a complementary one from your catalogue, with a short explanation. You still confirm it. There is a daily credit limit.
The discount is applied in the cart, only when the cart also contains a line on this plan. Buy the add-on on its own and it costs full price.
Under Subscription add-ons, attach reusable Groups or add one-off products under Individual with Add products. These are the products an existing subscriber can add to their next delivery from their account, unrelated to the featured add-on above.
Product page: Subscription Widget, then Customize widget on the active template and Display Settings. Tick Show add-on products in purchase widget. The tile carries a badge ("Special offer" by default) and a notice saying the add-on is not added to renewals.
Customer account: Settings → Customer Portal, turn on Add or remove one-time purchase products to upcoming orders.
A subscription can hold one active add-on at a time.
It is added as a line on the subscription and billed with the next order.
After that order bills successfully, the app removes the line, so it never renews.
An add-on line cannot be swapped for something else.
Add-ons do not apply to Mollie-billed subscriptions. Those are not Shopify subscription contracts, so they have no add-on section in the customer account and nothing is carried into a Mollie renewal.
Group the account add-ons once and reuse them across plans instead of listing products plan by plan.
Open a product page and check the add-on tile renders under the subscription options.
Stuck on any of this? Open the chat in the bottom right corner of the app and we will help you set it up.
