Last updated: December 17th, 2025
Each state has unique income tax withholding rules. Below are Montana's 2026 withholding instructions, including allowance calculations, standard deduction adjustments, and the percentage method for determining tax due.
Employers must also adhere to federal income tax withholding rules. More information can be found here about federal rates.
Alternatively, employers can automatically calculate payroll withholding by using ezPaycheck.
| State Abbreviation | MT |
|---|---|
| State Tax Withholding State Code | 30 |
| Acceptable Exemption Form | W-4 |
| Basis For Withholding | State Exemptions |
| Acceptable Exemption Data | S, M / Number of Exemptions |
| TSP Deferred | Yes |
| Special Coding | None |
| Additional Information | None |
| Official State Tax Website | Visit Official Website |
Montana's Form MW-4 allows allowances for personal exemptions and dependents. A single person claims 1 for themselves. A married person filing jointly can claim an additional 1 for their spouse (so 2 total for a couple) - typically only one spouse does this if both work. Each dependent gives 1 allowance. Montana does not explicitly have separate age or blindness allowances on the form. However, an extra allowance is permitted if the employee is a 'Surviving Spouse' filing status, akin to head of household - effectively treated similarly to married on the form.
| Component | Allowances | Notes |
|---|---|---|
| Yourself | 1 allowance | Base allowance |
| Spouse | 1 allowance | If filing jointly (typically only one spouse claims if both work) |
| Each Dependent | 1 allowance | Per dependent |
| Surviving Spouse | 1 allowance | Extra allowance for surviving spouse status |
Total Allowances = 1 (Self) + 1 (Spouse, if applicable) + Number of Dependents
Montana does not explicitly have separate age or blindness allowances on the form. Surviving Spouse status is treated similarly to married on the form.
For links to official state tax and revenue websites for all 50 states, visit our State and Local Tax Sites page.
Identify the employee's filing status. Montana uses codes: B = Married Single Income, H = Head of Household, J = Married Joint Dual Income, M = Married Single Income (similar to B), S = Single.
Determine the number of state exemptions from the W-4.
Calculate the employee's taxable income. Start from the gross annual wages and subtract any federally recognized exemptions or pre-tax contributions as per Montana guidelines.
Apply the Montana tax table based on the employee's filing status. Montana has progressive rates depending on taxable income ranges.
The tables show the base tax and the rate for excess amounts. Calculate the tax accordingly.
If paying biweekly, divide the annual tax by 26 to obtain the per-pay-period withholding.
Want to calculate in an easier way? Learn how to calculate Montana taxes via ezPaycheck below.
Learn More| If Taxable Income Is | Tax Withholding | ||||
|---|---|---|---|---|---|
| Over | But Not Over | Base | + | Rate | Of Excess Over |
| $0 | $16,100 | $0 | + | 0.00% | $0 |
| $16,100 | $63,600 | $0 | + | 4.70% | $16,100 |
| $63,600 | and over | $2,223 | + | 5.90% | $63,600 |
| If Taxable Income Is | Tax Withholding | ||||
|---|---|---|---|---|---|
| Over | But Not Over | Base | + | Rate | Of Excess Over |
| $0 | $24,150 | $0 | + | 0.00% | $0 |
| $24,150 | $95,400 | $0 | + | 4.70% | $24,150 |
| $95,400 | and over | $3,349 | + | 5.90% | $95,400 |
| If Taxable Income Is | Tax Withholding | ||||
|---|---|---|---|---|---|
| Over | But Not Over | Base | + | Rate | Of Excess Over |
| $0 | $32,200 | $0 | + | 0.00% | $0 |
| $32,200 | $127,200 | $0 | + | 4.70% | $32,200 |
| $127,200 | and over | $4,465 | + | 5.90% | $127,200 |
ezPaycheck simplifies payroll calculations, including Montana's withholding rules. Easily compute taxes, generate reports, and print paychecks or tax forms.
We strive to provide accurate and up-to-date Montana state tax information for 2026. If you notice any discrepancies, errors, or have questions about the tax rates or calculations shown on this page, please contact our support team. We appreciate your feedback and will review and update the information as needed.
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