Card Reference Field Settings Explained
This article explains the specific settings available for Card Reference fields in Amazing Fields. Once you've added a Card Reference field to your board, these settings control which cards users can link to and how multiple selections are handled.
Note: Card reference fields are available to supporters on the Advanced and Ultimate tiers. If you're on the free plan, upgrade to unlock this feature.
If you haven't yet added a Card Reference field, start with: Card Reference Fields in Amazing Fields for Trello.
Where to find card reference settings
After adding a Card Reference field (via Add > Advanced Fields > Card Reference), scroll down in the field editor to the Card Reference Settings section.

Available settings
Allow selecting multiple cards
By default, a Card Reference field allows the user to link only one card. Enable "Allow selecting multiple cards" if users should be able to link two or more cards in the same field. When multiple cards are selected:
- All linked card names appear as a list in the card details view.
- On the front of the card, names display as a comma-separated list.
For example, in the screenshot below, users can only select one customer but multiple team members.

Tip: Use this setting for fields like Team Members, Stakeholders, or Tags where multiple associations make sense. For fields like Customer or Owner, keep it off to enforce a single link.
Board (Card source board)
By default, users can select any card from the current board. Use the Board setting to point the field at a different board entirely. This is useful when your reference data lives on a dedicated board, for example:
- A Customer field that pulls from a Customers board.
- A Team Member field that pulls from an Employees board.
- A Product field that pulls from a Products catalogue board.

List(s) (Card source list filter)
By default, all cards on the selected board are available for selection. Use the List(s) setting to restrict the selectable cards to only those in one or more specific lists. This is useful for keeping dropdowns clean and relevant:
- Show only Active customers, not archived ones.
- Show only currently employed team members, not past staff.
- Show only In Stock products, not discontinued items.
You can select more than one list, for example, "Active" and "On Hold", to broaden the available options while still excluding fully archived cards.
Need help? If you get stuck with card reference field settings, use the help icon in Amazing Fields to get in touch with support.