Administrators may need to hide the Quick Create feature from their End Users for various business reasons.
The Quick Create feature allows users to create a new record quickly by entering just a few fields to create a new Account, Contact or Opportunity.
Administrators have the ability to hide the quick create section from all overview pages. This will prevent Users from creating new records without entering all required fields. At this time it is possible to hide the Quick Create sections from either all overview pages, or no overview pages. It is not possible to hide the quick create section from just one or two of the overview pages.
In Salesforce Classic:
In Lightning Experience:
This will hide the Quick Create section for all Users.
Note: The 'Show Quick Create' setting also affects whether or not Users can create new records from within the lookup dialog. For example, with the setting enabled, Users can create a new Account within the Account lookup dialog while creating or editing a Contact.
Creating new records in the lookup dialog is available only if Quick Create is available for the type of record being created. In addition, Users always need the appropriate 'Create' permission to use Quick Create, even though it will be displayed for all Users.
To remove the ‘Create New..’ section from the Home page only available in Classic:
In Classic:
Setup | Customize | Home Page Layouts, select Edit for a layout, deselect the box for Create New…, click Next, then Save.
Note: If the User is still able to see the Create New on the objects, then make sure under Setup | Customize | User Interface | under Sidebar section | option 'Show Custom Sidebar Components on All Pages' needs to be checked. The Create New option will not be visible to the Users.
Vote and comment on the Idea to Disable Quick Create 'New' button on lookup window in Lightning+Community UI.
See also
Create Records with Quick Create
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