The Tax Foundation's State Competitiveness Index reveals which states are taxpayer-friendly for both individuals and businesses. States are ranked based on income, sales, excise, property, capital gains, corporate, payroll, estate, and VAT consumption taxes.

In most respects, Idaho and Montana have been enthusiastic in their pursuit of tax competitiveness. But if there’s one area of tax policy on which they are worse than their peers, it’s in their incorporation of GILTI—the federal tax on Global Intangible Low-Taxed Income—into their own state tax codes. Not even California or Illinois does that.