Montana State Income Tax Withholding
Reference Number: NFC-26-1767632355
Published: March 27, 2026
Effective: Pay Period 05, 2026
Summary
The tax table and withholding formula for the State of Montana have changed.
No action on the part of the employee or the personnel office is necessary.
Tax Formula
|
State Abbreviation: |
MT |
|---|---|
|
State Tax Withholding State Code: |
30 |
|
Acceptable Exemption Form: |
MW-4 |
|
Basis for Withholding: |
State Exemptions |
|
Acceptable Exemption Data: |
S/M/MS/MB/HH |
|
TSP Deferred: |
Yes |
|
Special Coding: |
None |
|
Additional Information: |
None |
Withholding Formula (Effective Pay Period 05, 2026)
Note: The State does not allow employees to claim exemption from withholding on wages that are subject to withholding. If the employee has claimed exemption, but has taxable wages, calculate tax using the steps below.
- Subtract the nontaxable biweekly Thrift Savings Plan contribution from the gross biweekly wages.
- Subtract the nontaxable biweekly Federal Health Benefits Plan payment(s) (includes dental and vision insurance program, and Flexible Spending Account — health care and dependent care deductions) from the amount computed in step 1.
- Add the taxable biweekly fringe benefits (taxable life insurance, etc.) to the amount computed in step 2 to obtain the adjusted gross biweekly wages.
- Multiply the adjusted gross biweekly wages by the number of pay dates in the tax year to obtain the annual wages.
- Apply the annualized taxable wages to the table below based on marital status to determine the annual tax amount.
Single, Married Filing Separately, or Married Filing Joint with Both Spouses Working Taxable Wages
|
At Least |
Less Than |
Amount Of Tax |
|---|---|---|
|
$0 |
$16,100 |
$0 plus 0.0% over $0 |
|
$16,100 |
$63,600 |
$0 plus 4.7% over $16,100 |
|
$63,600 |
And Over |
$2,233 plus 5.65% over $63,600 |
Married Filing Jointly or Qualifying Widower Taxable Wages
|
At Least |
Less Than |
Amount Of Tax |
|---|---|---|
|
$0 |
$32,200 |
$0 plus 0.0% over $0 |
|
$32,200 |
$127,200 |
$0 plus 4.7% over $32,200 |
|
$127,200 |
And Over |
$4,465 plus 5.65% over $127,200 |
Head of Household Taxable Wages
|
At Least |
Less Than |
Amount Of Tax |
|---|---|---|
|
$0 |
$24,150 |
$0 plus 0.0% over $0 |
|
$24,150 |
$95,400 |
$0 plus 4.7% over $24,150 |
|
$95,400 |
And Over |
$3,349 plus 5.65% over $95,400 |
- Divide the annual Montana tax withholding by the number of pay dates in the tax year and round up to the nearest dollar.
- Add additional amount or percentage elected by the employee to the pay period tax calculated in the above step and round to the nearest dollar to determine the amount of tax to be withheld for the biweekly Montana tax withholding.
Resources
To view the updated tax formula, go to the HR and Payroll Clients page from the MyNFC drop-down menu on the National Finance Center (NFC) Home page. Select the Publications tab and select Taxes from the Publications Library section to launch the tax map. Select the desired state from the map provided for the formula.
Inquiries
For questions about NFC processing, authorized Servicing Personnel Office representatives should contact the NFC Contact Center at 1-855-NFC-4GOV (1-855-632-4468) or via the customer service portal at ServiceNow Portal for Federated Users and at ServiceNow Portal for Non-Federated Users.