snap bids vs cob

A snap bid is given the day of bid day, usually early in the morning and typically to girls who make it to round 3 @ the house. COB is continuous open bidding, so you have a longer time to explore the options and the house can get to know you within a few weeks or even the entire semester depending on which sorority

Adding on to the above,

Snap bids only happen if a house does not make quota during bid matching. Snaps bids go out before bid day starts and if a chapter misses quota but snaps up to quota, they are counted as making quota.

Houses are eligible for COB if they are below chapter total (kind of like average size). COB has nothing to do with quota. A top chapter could have a bunch of December graduates and fall under total during the spring semester and COB. Usually houses that are a lot under total will hold informal rush events, and houses that are just a few under will discreetly extend bids to close friends of members.