Do all sororities do cob? A comprehensive guide to Continuous Open Bidding

September 24, 2025 •

3 min read

A common misconception about sorority recruitment is that all chapters participate in Continuous Open Bidding (COB); however, this is not the case. It's a more informal, opportunistic process dependent on whether a chapter has spots to fill, unlike the structured formal recruitment period everyone knows.

Quick Summary

Not all sororities engage in Continuous Open Bidding (COB) because participation is limited to chapters that have fallen below the campus-set membership capacity, known as chapter total. This means a chapter's eligibility and decision to participate can vary semester to semester, creating a less predictable path to membership than formal recruitment.

Key Points

Not Universal: Only sororities with membership numbers below the campus-set 'chapter total' are eligible to participate in Continuous Open Bidding (COB) [2, 3].
Informal Process: COB is more relaxed and less structured than formal recruitment, involving casual events and individual invitations [2, 3].
Eligibility Changes: A chapter's eligibility to participate in COB can change from semester to semester based on its membership numbers [2].
Proactive Effort: Interested students must be proactive in finding out which chapters are holding COB by checking Panhellenic websites, social media, or speaking to members [2, 1].
No Guarantee: There is no guarantee of receiving a bid through COB, and the number of bids offered can be very limited [2].
Different Timing: COB can happen at various points in the semester, not on a single designated bid day like formal recruitment [2].

What is Continuous Open Bidding (COB)?

Continuous Open Bidding, or COB, offers a less structured path to joining a sorority compared to formal recruitment [2, 3]. It's an informal process that allows chapters to extend membership invitations, known as bids, outside of the main recruitment period [3]. COB often involves casual gatherings and one-on-one interactions [2].

The Informal Recruitment Process

COB is driven by individual chapters rather than a central Panhellenic council [2]. Chapters eligible for COB reach out to potential new members (PNMs) who have shown interest [2]. Events are relaxed, such as casual meals or small social activities [2]. Bids can be extended at various times throughout the semester [2].

Why Don't All Sororities Participate in COB?

The primary reason not all sororities participate in COB is related to 'chapter total' [2, 3]. Chapter total is the maximum membership size set for each sorority by the campus Panhellenic Council [2, 3]. Only chapters with membership numbers below this total are allowed to offer bids through COB [2, 3].

Chapter Total Explained

Chapter total is typically calculated based on the average size of all sorority chapters on campus [2]. If a chapter's membership drops below this average, it becomes eligible to participate in COB [2]. Reasons for being below total include members graduating, transferring, or becoming inactive [2]. Consequently, a chapter's eligibility for COB can change each semester [2].

How to Find Out Which Sororities are Doing COB

Since COB is informal and not universally practiced, finding participating sororities requires active effort [2].

A Step-by-Step Guide for Potential Members

Check the Campus Panhellenic Website: Your college's Panhellenic Council website is the most reliable source for a list of eligible chapters and potential interest forms [2, 1].
Follow Sorority Social Media: Many chapters announce COB plans on platforms like Instagram [2]. Follow campus Panhellenic and individual chapter accounts [2].
Talk to Chapter Members: If you know members of a sorority, ask about their chapter's COB plans; they might connect you with the recruitment chair [2].
Attend Campus Greek Life Events: Some campuses hold informal events outside of formal recruitment that can be opportunities to learn about COB [2].

Comparing COB and Formal Recruitment

COB differs significantly from formal recruitment in several aspects [2, 3].


Feature	Continuous Open Bidding (COB)	Formal Recruitment
Timing	Occurs informally throughout the semester [2, 3].	A multi-day, structured event, typically at the start of a semester [2, 3].
Eligibility	Limited to chapters below chapter total [2, 3].	All chapters participate [2, 3].
Events	Casual, unstructured gatherings [2, 3].	Highly structured, organized events [2, 3].
Bids	Chapters extend bids directly on their own timeline [2].	Bids are distributed on a single designated 'bid day' [2].
Cost	Usually free to participate [2].	Typically requires a registration fee [2].
Number of Bids	Varies widely, can be limited [2].	Quotas aim to ensure a certain number of bids from each chapter [2].

The Ins and Outs of the COB Timeline

COB does not follow a strict timeline [2]. Chapters initiate COB based on their needs, which can happen weeks or months into the semester [2]. This means PNMs need patience and persistence [2]. While some Panhellenic councils provide general COB periods, specific chapter timelines vary [2].

Tips for Succeeding in the COB Process

To increase your chances with COB, consider these tips:

Express genuine interest: Be authentic and let your personality show in the more personal COB interactions [2].
Reach out directly: Contact chapter recruitment chairs or members through email or social media [2].
Maintain strong academics: Good grades are often a requirement and make you a stronger candidate [2].
Engage with chapter members: Referrals from current members are valuable during COB [2].

For campus-specific details, consult your Panhellenic Council website. The Auburn University Panhellenic website provides a good example of local COB information [1].

Continuous Open Bidding vs. Your Other Options

COB is one path to joining a sorority, suitable for those who missed formal recruitment or prefer a less intense process [2]. However, it's not a guaranteed route [2]. If your heart is set on a specific chapter that is at or above chapter total, waiting for the next formal recruitment might be necessary [2]. Exploring all options and managing expectations is key [2].

Conclusion

To reiterate, not all sororities participate in COB [2]. This informal process is only available to chapters that are below their set membership total [2, 3]. Unlike the structured formal recruitment, COB is less predictable, driven by individual chapter needs and timelines [2]. Potential new members interested in COB should be proactive in their research and engagement to find opportunities to connect with eligible chapters [2]. Understanding the distinct nature of COB is essential for navigating this alternative path to sorority membership [2].

Frequently Asked Questions

COB stands for Continuous Open Bidding. It refers to the informal recruitment process that National Panhellenic Conference (NPC) sororities can use to recruit new members outside of the formal recruitment period, provided they have space available [2, 3].

You can find out by checking your campus Panhellenic Council's official website, filling out an interest form if available, and following the social media accounts of both the Panhellenic Council and individual sorority chapters [2, 1].

Yes, for the most part. Continuous Open Bidding is the technical term for the informal recruitment process used by Panhellenic sororities. The two terms are often used interchangeably [2, 3].

No, not all sororities do COB in the fall. Only chapters that are under the campus-mandated membership total are eligible, and even then, participation is not mandatory and can change yearly [2].

Generally, yes, it can be more challenging to get a bid through COB. The process is often more competitive because fewer bids are available, and not all chapters participate. It's also less structured, so personal connections can play a larger role [2].

Yes, you can typically participate in events and get to know multiple sororities during the COB period. However, you can only accept a bid from one sorority [2].

Benefits include a more laid-back and personal recruitment experience, an opportunity to join if you missed formal recruitment, and the chance to meet members and learn about a chapter's culture in a less overwhelming setting [2].

COB events are typically more casual than formal recruitment. Think of it as dressing for a nice casual event or a first date. It's best to wear something comfortable yet polished, like jeans and a nice top or a simple dress [2].