When you create a SmartPass Link the information required to create a unique pass is stored in the URL. When a user clicks on the URL the PassKit system decrypts the URL and creates the pass, populating the dynamic fields with the data in the URL.
The same SmartPass Link can be used multiple times to create passes, all with the same data, but each one with a unique Pass ID. This means it is possible for one user to have multiple cards from your organisation stored in their Wallet, all from clicking one SmartPass Link.
It may be that you only want a user to have one pass, you can do this by adding a unique ID to the customer data, in this case if the user clicks on the SmartPass Link a second time, then the pass created on the first click will be displayed. This is because when the SmartPass link is clicked a check is made to see if a pass already exists containing the Unique ID, and if it does, then this pass is then displayed instead of a new pass being created.
How to add a Unique ID
To set up this feature you need to enable the setting 'Auto fill External ID'. For information on how to do this, please see the help article here
When done, the email or phone number for the member will also be added to the External ID field for the member, as this field must have a unique value it can be used to prevent a new pass being created when the SmartPass Link is clicked for a second time.
First, we can check the behaviour of the SmartPass Link without the Unique ID being enabled.
Next I will upload my CSV to generate the SmartPass Links
Let's follow the link for Percy PassKit, the pass is created, let's take a look. Take note of the Pass Id displayed beneath the QR code.
Next I will follow the same link, please note the next pass created will have a different Pass ID
If we take a look at the Member List in the portal we can see that there are two separate members, that have been created from one SmartPass Link
And if we look at the members details, we can see that the External ID is not populated.
Now I will enable the autofill option in the settings, In this example I will use the email address as the unique ID
I will now follow the SmartPass Link for Laura Loopy.
If I now look in the Member List in the portal I can see my new member, and if I look at the member details I can see the External ID field has been populated.
Now, every time the SmartPass Link is clicked, the original pass (with the same Pass Id) will be shown.
You can test this behaviour by following this SmartPass Link
The URL you will be directed to will always be