Campayn does have a multi-user account!Here are
This feature is reserved for users with Unlimited Plan.
Once you select Unlimited in the Plan section a new row will appear.
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Once you click on the new row, some new options will appear where you can choose the tier of the multi user feature. Have in mind that this is an addition to your existing plan and not a part of it cost wise.
Once you upgrade, you will notice the “Manage Contacts” menu item has been added to the Settings page.
You can check the feature overview here: https://www.campayn.com/multi-user
Here is a list of some of Campayn's multi-user account features:
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The sub-users need to import lists individually as they do not share the contacts, only the contact limit.