# How are Bidder IDs assigned?

> Source: https://support.associationsphere.com/how-are-bidder-ids-assigned  |  Updated: 2024-04-08T19:26:30Z

1.  Bidder IDs can be created two ways:

a.  As a unique constituent (actual attendee) at an event linked to an auction.

b.  By registering for the auction from the auction page, if they are creating a new constituent and portal account.

2.  Bidder IDs are only assigned to unique constituents.

3. Two different constituents cannot share the same Bidder ID.