FeatureKarl Frieden Awarded for Excellence in State Taxation by COST September 24, 2026

The COST Board was pleased to announce at COST’s 57th Annual Meeting in San Antonio, Texas that Karl Frieden is the recipient of the 2026 COST/Paul Frankel Excellence in State Taxation Award. 

Feature2025 State and Local Business Tax Burden Study December 30, 2025

The Council On State Taxation (COST) and the State Tax Research Institute (STRI) are pleased to announce the release of the 23^rd annual study of state and local business taxes. The report, “Total State and Local Business Taxes: State-by-State Estimates for Fiscal Year 2024,” prepared by Ernst & Young LLP, shows all state and local business taxes paid in each of the 50 states and the District of Columbia. 

Businesses paid $1.15 billion in state and local taxes in FY2024, an increase of 4.5% from FY2023. State business taxes increased by 3.6%, and local business taxes grew by 5.5%. In FY2024, business tax revenue accounted for 45.8% of all state and local tax revenue. 

Feature2025 Year In Review December 19, 2025

As the close of 2025 draws near, we would like to thank our industry members, practitioner partners, state chamber and taxpayer association partners and others in the state and local tax community for the support in our mission.  A listing of our activity has been compiled.

FeatureTracking Chart: State and Local Disaster Relief Guidance August 27, 2026

COST is tracking state and local tax relief guidance in response to fires and other natural disasters.

FeatureRevisiting the Debate Over State Taxation Of Foreign-Source Income (Tax Notes State, June 23, 2025) June 23, 2025

In this article, COST’s Karl Frieden and Doug Lindholm analyze California’s proposed digital advertising tax (DAT), comparing it with the existing Maryland DAT, and provide their rebuttal to Darien Shanske’s and Young Ran (Christine) Kim’s flawed characterization of and justification for the California DAT legislation as a digital barter tax. This article is a follow up to Frieden and Lindholm’s article on “State Digital Services Taxes: A Bad Idea Under Any Theory” that appeared in Tax Notes State on April 10, 2023. 

FeatureThe Mobile Workforce Act Introduced in the U.S. Senate April 10, 2025

Senate Majority Leader John Thune (R-SD) and Senator Catherine Cortez Masto (D-NV) today announced their introduction of the Mobile Workforce State Income Tax Simplification Act of 2025, S. 1443, which would set a uniform 30-day threshold before employees who travel across state borders for work become subject to personal income tax filing in nonresident states, and their employers on corresponding withholding obligations. For over a decade, COST and over 300 other organizations and businesses led efforts in the Congress towards enactment of the Mobile Workforce Act and since 2019, COST has simultaneously been engaged in state-by-state efforts to combat the patchwork of state laws governing the taxation of nonresident traveling workers.

FeatureThe Boomerang Effect of the Business ‘Fair Share’ Tax Debate (Tax Notes State, February 10, 2025) February 10, 2025

In this article, COST’s Karl Frieden and Doug Lindholm analyze California’s proposed digital advertising tax (DAT), comparing it with the existing Maryland DAT, and provide their rebuttal to Darien Shanske’s and Young Ran (Christine) Kim’s flawed characterization of and justification for the California DAT legislation as a digital barter tax. This article is a follow up to Frieden and Lindholm’s article on “State Digital Services Taxes: A Bad Idea Under Any Theory” that appeared in Tax Notes State on April 10, 2023.