Upcoming National Meeting

57th Annual Meeting

The Annual Meeting offers sessions for every state tax and government affairs professional with tax responsibilities. The Meeting has an extensive program covering all types of state and local taxes that business taxpayers are confronted with on a daily basis. The ever-popular audit sessions and state chamber of commerce roundtables are included, and other conference sessions provide updates on

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Newsletters & Media

Legislative Alert

ISSUE 26-27; July 15, 2026

Arizona Unclaimed Property Legislation Removes Key Exemptions; Pennsylvania Digital Ad Tax and Mandatory Combined Reporting Not Expected to Advance

Cost Conscious

ISSUE 26-15; July 24, 2026

AI Tools for SALT Professionals – On July 14 & 16, COST hosted its AI Learning Series for SALT Professionals. This two-part webinar series was designed to help SALT professionals understand and confidently apply AI in their day-to-day responsibilities. We would like to gain a better understanding of how members are currently using artificial intelligence in their state and local tax functions and

Featured Resources

COST - Council on State Taxation

Amicus Briefs

AT&T Mobility, LLC v. Board of Supervisors of Lamar County, Mississippi

COST filed an amicus brief requesting the Supreme Court of Mississippi to accept an interlocutory appeal to address both the legality of, and constitutional issues with, a county assessor’s property tax valuation of a telecommunications company’s personal property. The brief pointed out concerns with the assessor not following the State’s valuation process which for industrial personal property is

COST - Council on State Taxation

COST Studies, Articles & Reports

2026 State and Local Amnesty Programs

Tracker of most state and local tax amnesty programs enacted and conducted in 2026.

COST - Council on State Taxation

COST Comments & Testimony

Comment Letter in Support of Rolling Stock Exemption, H. 5518

COST submitted a letter to the members of a Massachusetts House-Senate Conference Committee, in support of Sections 22A – 22D of the environmental bond bill H. 5518, which would exempt the rolling stock of common carriers from Massachusetts sales and use tax. COST's letter encourages lawmakers to expand this exemption to include all rolling stock used in operations of all businesses.