FeatureHollis Hyans Awarded for Excellence in State Taxation by COST September 17, 2025

The COST Board was pleased to announce at COST’s 56th Annual Meeting in Memphis, Tennessee that Hollis Hyans is the recipient of the 2025 COST/Paul Frankel Excellence in State Taxation Award. 

Feature2026 COST Events...At A Glance October 6, 2025

Now is a great time to start planning your conference attendance for 2026!

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. 

Feature2026 COST Events...At A Glance October 6, 2025

Now is a great time to start planning your conference attendance for 2026!

Feature2024 State and Local Business Tax Burden Study December 20, 2024

The Council On State Taxation (COST) and the State Tax Research Institute (STRI) are pleased to announce the release of the 22^nd annual study of state and local business taxes. The report, “Total State and Local Business Taxes: State-by-State Estimates for Fiscal Year 2023,” 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 $1,096.2 billion in state and local taxes in FY2023, an increase of 3.7% from FY2022. State business taxes increased by 0.9%, and local business taxes grew by 7.3%. In FY2023, business tax revenue accounted for 44.7% of all state and local tax revenue. 

FeatureTracking Chart: State and Local Disaster Relief Guidance December 19, 2024

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

FeatureIs E-Invoicing Relevant In The US State Sales Tax Context? May 23, 2024

The Council On State Taxation (COST) and the State Tax Research Institute (STRI) are pleased to announce the release of the study, “Is e-invoicing relevant in the US state sales tax context?”  This study, prepared by EY Quantitative Economics and Statistics Group (QUEST), explores the rise of e-invoicing in tax administration in dozens of value-added tax (VAT) systems around the world and analyzes e-invoicing from a U.S. state tax policy perspective. The study highlights key differences between VAT and U.S. state sales tax systems that make e-invoicing less relevant in the United States.

FeatureWearing Blinders in the Debate Over Business’s ‘Fair Share’ of State Taxes (Tax Notes State, April 8, 2024) April 8, 2024

In this article, Karl Frieden rebuts the central thesis of the Tax Notes State roundtables of Dan Bucks, Peter Enrich, Michael Mazerov, and Darien Shanske that business does not pay its fair share of state and local taxes. He does so by using their own criteria for measuring “fair share” based on deviations from optimal or neutral tax design to show that business “overpayments” of sales and excise taxes on business inputs and property taxes on business property are 15 times or more greater than the roundtable members’ assertion of business “underpayments” of state corporate income tax.

FeatureCOST & STRI Release Paper Evaluating Mandatory Worldwide Combined Reporting March 8, 2024

We are pleased to share our latest paper documenting the harmful and unnecessary implications surrounding state adoption of mandatory worldwide combined reporting (MWWCR), by Douglas L. Lindholm and Marilyn A. Wethekam. 

FeatureDigital-Business Input Exemptions: Lessons from Sales Tax History January 29, 2024

COST’s Karl Frieden and Fred Nicely discuss how to design a sales tax system that exempts digital business inputs by looking back to states’ adoption of sales taxes in the 1930s and 1940s and the approaches to avoiding tax pyramiding in the manufacturing sector. This article is a follow up to the article Karl and Fred authored with Priya Nair on “Down the Rabbit Hole: Sales Taxation of Digital Business Inputs."

FeatureCOST Scorecard: The Best and Worst of State Tax Administration (2023) December 29, 2023

The Council On State Taxation (COST) is pleased to release its 2023 Scorecard on state tax appeals processes and administrative practices. This eighth Administrative Scorecard continues to apply objective criteria to evaluate independence in tax appeals systems and key procedural elements that impact taxpayers’ perceptions of fairness and efficiency.

Feature2024 State and Local Business Tax Burden Study December 20, 2024

The Council On State Taxation (COST) and the State Tax Research Institute (STRI) are pleased to announce the release of the 22^nd annual study of state and local business taxes. The report, “Total State and Local Business Taxes: State-by-State Estimates for Fiscal Year 2023,” 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 $1,096.2 billion in state and local taxes in FY2023, an increase of 3.7% from FY2022. State business taxes increased by 0.9%, and local business taxes grew by 7.3%. In FY2023, business tax revenue accounted for 44.7% of all state and local tax revenue. 

FeatureMinnesota's New Approach to Taxing Foreign Income Is Unfair and Unwise (Tax Notes State, August 21, 2023) August 21, 2023

COST's Karl Frieden and Fred Nicely examine how Minnesota’s new approach to taxing foreignsource income is unfair to U.S. multinationals, uncompetitive with other states, and likely violates the commerce clause based on U.S. Supreme Court precedents concerning discrimination, fair apportionment, and foreign commerce.