member benefits

Why Join COST?

Click here to download the COST Prospective Member Document.

Company Member Benefits

Membership in COST is exclusive - only multistate companies that are not engaged in the business of tax advising or consulting may apply for membership.  When your company joins COST, every employee of the company benefits – including employees outside of the tax department, such as government affairs and legal.  That effectively means multiple memberships for the price of one.  COST offers many resources to help each member make the most of their investment and connect with the benefits they value most.  The annual dues allow your company employees to: participate in COST's renowned conferences and schools; access a national network of corporate state tax professionals sharing technical knowledge; and shape and benefit from COST's legislative, regulatory and judicial advocacy.

Membership Dues Structure

Annual Revenue Dues Rate
Less than $2 Billion $3,000
$2 Billion - $25 Billion $5,000
Over $25 Billion $7,000

*Annual revenues are based on all affiliates served by the corporate tax department.

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What Does COST Offer?


COST offers its members high quality education, including conferences, schools, regional meetings and special symposia, featuring the hottest topics, delivered by the nation's most recognized experts, at a price well below comparable programs.  In fact, all COST conferences and seminars are priced at break-even.  Attendees at our conferences find a relaxed atmosphere in which to interact with professional peers, free from solicitation pressures by tax consultants.  The majority of COST programs qualify with state boards of accountancy and state bar associations for continuing education credits.

COST events include:

  • SALT Basics School
  • Sales Tax Conference and Audit Session
  • Spring Audit Session and Income Tax Conference
  • Intermediate/Advanced Sales and Use Tax School
  • Intermediate/Advanced State Income Tax School
  • Annual Meeting (including Members-Only Audit Sessions, Tax Policy Conference & Legal Symposium)
  • Approximately 30 Regional Meetings held in cities throughout the U.S.


One of the most often cited reasons for joining COST is the opportunity to network with other state tax professionals.  The experienced state tax professional knows that the answers to the many different state tax questions are often not available through research, but are based upon years of experience and discussions with peers.  COST promotes networking opportunities through its online member forum and at COST conferences and schools.


COST's advocacy program is oriented toward active involvement on state tax issues of broad importance to the membership.  COST advocates on behalf of its membership in the legislative, judicial and administrative arenas.  State and local government policymakers rely heavily on COST staff in formulating, implementing, and changing the state tax landscape.  COST's reputation as the nationwide voice of corporate taxpayers has garnered respect from the leadership of the National Conference of State Legislatures, the Federation of Tax Administrators, the National Governors Association, and even the Multistate Tax Commission.  COST's involvement in an issue on behalf of its corporate membership signals to state leaders that the issue is one of importance.  COST also serves as a resource on business tax issues to other organizations, including State Chambers of Commerce and state taxpayer associations, as those groups develop strategies to address complex state tax matters.

Specifically, the COST team disseminates information on pertinent legislative, judicial and regulatory developments through regular publications, and coordinates advocacy activities with members and other sympathetic parties.  COST staff files amicus briefs with state and federal courts, provides testimony (oral and written) before legislative and administrative bodies, meets with state policymakers, and brings together interested members to enhance advocacy activities on targeted issues.

COST staff also furthers COST's advocacy agenda through frequent participation as speakers at all national state and local tax conferences, state department of revenue conferences, individual state chamber of commerce and other business organization conferences, and, of course, all COST-sponsored national and regional meetings.  These programs provide the opportunity for COST staff to both promote COST's advocacy agenda to a wide audience and network with COST members and other interested parties on a frequent basis.


For more than 40 years, COST has been a leading source for state tax information critical to its members.  COST members use a variety of ways to stay connected to industry information, including publications, newsletters, exclusive website content, forums, special reports, and current development outlines.  Members have access to up-to-date information when they need it.

"COST has been a tremendous resource for myself and my company.  In attending the COST meetings I return back to my company with various issues to research that could add value to my tax department.  I frequently use the COST member forum and the COST members as a resource for audit and controversy issues for insight I might not have considered.  This is a fantastic organization and I’m proud to belong to."  Mike Halleron - Tribune Company, Chicago, IL

For questions regarding membership, please contact Judy Slotnik   (202/484-5227).