If a product offers both a one-time purchase and a subscribe-and-save option, show a small "Upgrade to subscription and save X%" prompt directly inside the cart line item. One tap converts the line into a subscription.

Requires a subscription app to be installed and active:

The app reads the subscription options Shopify exposes for that product — it doesn't create the subscription itself.

Configurable per language. Default: "Subscribe and save {discount}%". Localize for each market in your store.

Consumables — coffee, supplements, pet food, beauty refills — where customers reorder predictably. Less effective on one-off categories.