TAXES 18-28, Idaho State Income Tax Withholding
Published: March 21, 2018
Effective: Pay Period 20, 2017
Summary
This tax bulletin is being updated to remove the number of pay periods in steps 4 and 7 and replace with the phrase "number of pay dates in the tax year," thereby preventing any confusion in future years. All other information in this bulletin remains the same.
No action on the part of the employee or the personnel office is necessary.
Tax Formula
State Abbreviation: |
ID |
State Tax Withholding State Code: |
16 |
Acceptable Exemption Form: |
W-4 |
Basis for Withholding: |
State or Federal Exemptions |
Acceptable Exemption Data: |
S/M, Number of Exemptions |
TSP Deferred: |
Yes |
Special Coding: |
None |
Additional Information: |
If a State income tax certificate has not been processed or a valid State exemption code is not present, the Federal exemptions will be used in the computation of State taxes. |
Withholding Formula (Effective Pay Period 20, 2017)
- 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 (i.e., taxable life insurance) 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 gross annual wages.
- Determine the exemption allowance by applying the following guideline and subtract this amount from step 4:
Exemption Allowance = $4,050 x Number of Exemptions
- Apply the taxable income computed in step 5 to the following table to determine the annual Idaho tax withholding:
Single - Tax Withholding Tables
If the Amount of Taxable Income Is:
The Amount of Idaho Tax Withholding Should Be:
Over $0 but not over $2,300
$0.00
Over $2,300 but not over $3,772
1.6% of excess over $2,300
Over $3,772 but not over $5,245
$24.00 plus 3.6% of excess over $3,772
Over $5,245 but not over $6,717
$77.00 plus 4.1% of excess over $5,245
Over $6,717 but not over $8,190
$137.00 plus 5.1% of excess over $6,717
Over $8,190 but not over $9,662
$212.00 plus 6.1% of excess over $8,190
Over $9,662 but not over $13,343
$302.00 plus 7.1% of excess over $9,662
Over $13,343
$563.00 plus 7.4% of excess over $13,343
Married - Tax Withholding Tables
If the Amount of Taxable Income Is:
The Amount of Idaho Tax Withholding Should Be:
Over $0 but not over $8,650
$0.00
Over $8,650 but not over $11,594
1.6% of excess over $8,650
Over $11,594 but not over $14,540
$47.00 plus 3.6% of excess over $11,594
Over $14,540 but not over $17,484
$153.00 plus 4.1% of excess over $14,540
Over $17,484 but not over $20,430
$274.00 plus 5.1% of excess over $17,484
Over $20,430 but not over $23,374
$424.00 plus 6.1% of excess over $20,430
Over $23,374 but not over $30,736
$604.00 plus 7.1% of excess over $23,374
Over $30,736
$1,127.00 plus 7.4% of excess over $30,736
- Divide the annual Idaho tax withholding calculated in step 6 by the number of pay dates in the tax year and round to the nearest dollar to obtain the biweekly Idaho tax withholding.
- 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.
Resources
To view the updated tax formula, go to the
page from the drop-down menu on the National Finance Center (NFC) homepage. Select the tab and select from the menu 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
or via the customer service portal.