You can limit a subscription plan so that each customer can hold only one subscription to it at a time. Turn on One per customer on the plan's page, and Shopify checkout refuses an order that would give a customer a second subscription to that plan. Your other plans are not affected.
Which plans can be limited to one per customer?
The One per customer card is on the create and edit pages of four plan types: Subscribe & save, Build a box, Fixed bundle and Mystery box. It is off on every plan until you turn it on, and you turn it on for each plan separately.
How do I turn on One per customer for a plan?
Open the plan's page in Subi.
In the right column, click the One per customer card. On Subscribe & save, Fixed bundle and Mystery box plans it sits under the Free shipping card; on Build a box plans, under the Preview card.
Check Limit this plan to one per customer.
Optionally write your own checkout messages (see below), then click Save in the window.
Click Save on the plan page. The card now reads On.
What does checkout refuse when One per customer is on?
When the plan is limited to one per customer, checkout does not complete and shows your message in these cases:
The cart holds more than one of the plan: two boxes of the same box plan, or the same subscription at quantity 2.
A customer who is logged in already has an active or paused subscription to the plan and tries to buy one more.
These still go through: one box that holds several items, a box together with a subscription to another plan, and one-time purchases. A guest who is not logged in is not recognised, even with the email of an existing subscriber.
Your product and cart pages do not change. The message appears only at checkout.
Can I change the message shoppers see at checkout?
Yes. After checking the box, two fields appear, so you can write each message in your store's language:
When the cart holds more than one: if left blank, shoppers read "You can have only one of this subscription. Remove the extra one to continue."
When the customer already has this plan: if left blank, shoppers read "You already have this subscription. You can manage it in your account."
Click Preview what shoppers see at checkout to see how each message looks at checkout before you save.
What happens to customers who already have more than one subscription?
Nothing changes for existing subscriptions. A customer who already has two subscriptions to the plan keeps both; checkout only refuses a new one.
Products added or quantities raised in the customer portal follow your Customer permissions.
Why does the One per customer card show a warning?
If checkout cannot apply the limit, the card stays On and shows a warning:
"Please update the app to access 'One per customer' and continue here." Subi needs one more permission for checkout rules. Click Update now and approve it.
Your store already runs the most checkout rules Shopify allows. Shopify allows 25 checkout rules per store. Turn one off in Shopify under Settings > Checkout > Checkout rules, then open the plan again.
Our rule is turned off in Shopify. Subi's rule is called "Subi: one per customer". Turn it on again in Shopify under Settings > Checkout > Checkout rules.