Sources
These publications and official references support the rules used in Valanta's available estimates.
About this list
A listed source may cover more than Valanta currently calculates. See How it works for calculation methods, state coverage, and exclusions. A jurisdiction not listed below is not yet included in the calculator; that page explains current coverage.
| Source | Publisher |
|---|---|
| Revenue Procedure 2025-32Federal, 2026 | Internal Revenue Service |
| Publication 505 (2026), Tax Withholding and Estimated TaxFederal, 2026 | Internal Revenue Service |
| IRS releases tax inflation adjustments for tax year 2026, including amendments from the One, Big, Beautiful BillFederal, 2026 | Internal Revenue Service |
| Publication 15 (2026) Employer's Tax GuideFederal, 2026 | Internal Revenue Service |
| Instructions for Form 8959 (Additional Medicare Tax)Federal, 2026 | Internal Revenue Service |
| Source | Publisher |
|---|---|
| Form 40NR booklet (federal income tax deduction line)Alabama, 2025 | Alabama Department of Revenue |
| What is Alabama's Individual Income Tax Rate?Alabama, 2026 | Alabama Department of Revenue |
| Alaska Tax FactsAlaska, 2026 | Alaska Department of Commerce Community and Economic Development - Office of the State Assessor |
| Individual Income Tax HighlightsArizona, 2026 | Arizona Department of Revenue |
| Withholding CalculationsArizona, 2026 | Arizona Department of Revenue |
| 2025 California Tax Rate Schedules (Form 540)California, 20252025 source used in 2026 estimates. | California Franchise Tax Board |
| 2026 Form 540-ES Estimated Tax InstructionsCalifornia, 2026 | California Franchise Tax Board |
| Form CT-1040ES (Rev. 01/26) tax tablesConnecticut, 2026 | Connecticut Department of Revenue Services |
| House Bill 13, amending 30 Del. C. section 1102(a)(15)Delaware, 2026 | Delaware General Assembly |
| Do I have to file a personal income tax return in Florida?Florida, 2026 | Florida Department of Revenue |
| Important Tax UpdatesGeorgia, 2026 | Georgia Department of Revenue |
| Tax Year Information 2025 (income tax rate schedules)Hawaii, 20252025 source used in 2026 estimates. | Hawaii Department of Taxation |
| Individual Income Tax Rate ScheduleIdaho, 20252025 source used in 2026 estimates. | Idaho State Tax Commission |
| Income Tax RatesIllinois, 2026 | Illinois Department of Revenue |
| What is the Illinois personal exemption allowance?Illinois, 2026 | Illinois Department of Revenue |
| Departmental Notice 1 (Indiana withholding)Indiana, 2026 | Indiana Department of Revenue |
| DOR: Rates, Fees and PenaltiesIndiana, 2026 | Indiana Department of Revenue |
| IDR Announces 2026 Individual Income Tax and Interest RatesIowa, 2026 | Iowa Department of Revenue |
| Iowa Income Tax (Legislative Services Agency)Iowa, 2026 | Iowa Legislative Services Agency |
| Kansas 2026 Individual Estimated Tax (Form K-40ES)Kansas, 2026 | Kansas Department of Revenue |
| 2026 Individual Income Tax RateKentucky, 2026 | Kentucky Department of Revenue |
| Employer Payroll WithholdingKentucky, 2026 | Kentucky Department of Revenue |
| Individual Income Tax Forms 2026 (tax rate schedules)Maine, 2026 | Maine Revenue Services |
| State Individual Income Tax Rate for 2026 Tax Year DeterminedMichigan, 2026 | Michigan Department of Treasury |
| Minnesota Income Tax Rates and BracketsMinnesota, 2026 | Minnesota Department of Revenue |
| General Information (individual income tax rate schedule)Mississippi, 2026 | Mississippi Department of Revenue |
| 2025 Individual Income Tax Year ChangesMissouri, 20252025 source used in 2026 estimates. | Missouri Department of Revenue |
| Nebraska Revised Statute 77-2715.03 (Individual Income Tax Brackets and Rates)Nebraska, 2026 | Nebraska Legislature |
| Income Tax in NevadaNevada, 2026 | Nevada Department of Taxation |
| Repeal of NH Interest and Dividends Tax Now in EffectNew Hampshire, 2026 | New Hampshire Department of Revenue Administration |
| NJ Income Tax Rates and Tax Rate SchedulesNew Jersey, 2026 | New Jersey Division of Taxation |
| Personal Income Tax RatesNew Mexico, 2026 | New Mexico Taxation and Revenue Department |
| New York State withholding tax tables and methods (NYS-50-T-NYS)New York, 20252025 source used in 2026 estimates. | New York State Department of Taxation and Finance |
| Tax Rate SchedulesNorth Carolina, 2026 | North Carolina Department of Revenue |
| Withholding Rates and Instructions for Wages Paid in 2026North Dakota, 2026 | North Dakota Office of State Tax Commissioner |
| House Bill 2764 fiscal impact statement (2025 Oklahoma income tax reform)Oklahoma, 2026 | Oklahoma Legislature |
| 2025 Form OR-40 instructions (Tax Rate Charts S and J)Oregon, 20252025 source used in 2026 estimates. | Oregon Department of Revenue |
| Tax RatesPennsylvania, 2026 | Pennsylvania Department of Revenue |
| Advisory 2025-22, 2025 Inflation Adjustments (Uniform Tax Rate Schedule for Tax Year 2026)Rhode Island, 2026 | Rhode Island Division of Taxation |
| Information about H. 4216South Carolina, 2026 | South Carolina Department of Revenue |
| TaxesSouth Dakota, 2026 | South Dakota Department of Revenue |
| Hall Income TaxTennessee, 2026 | Tennessee Department of Revenue |
| Business ClimateTexas, 2026Documented secondary-official source; not the state's own tax authority. | Office of the Texas Governor |
| 2026 Vermont Tax Tables and Rate SchedulesVermont, 2026 | Vermont Department of Taxes |
| Code of Virginia Title 58.1 Chapter 3 (Individual Income Tax)Virginia, 2026 | Virginia General Assembly (Legislative Information System) |
| DeductionsVirginia, 2026 | Virginia Department of Taxation |
| Income TaxWashington, 2026 | Washington Department of Revenue |
| West Virginia Code 11-21-4i (Rate of tax)West Virginia, 2026 | West Virginia Legislature |
| Wisconsin Tax Rates (individual income tax rate schedules)Wisconsin, 20252025 source used in 2026 estimates. | Wisconsin Department of Revenue |
| Business ResourcesWyoming, 2026Documented secondary-official source; not the state's own tax authority. | Wyoming Business Council |