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Idaho State Income Tax Information

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 if a valid state exemption code is not present, the Federal exemptions will be used in the computation of state tax.
Withholding Formula (Effective Pay Period 13, 2005)
  1. Subtract the nontaxable biweekly Thrift Savings Plan contribution from the gross biweekly wages.

  2. Subtract the nontaxable biweekly Federal Health Benefits Plan payment(s) (includes flexible spending account - health care and dependent care deductions) from the amount computed in step 1.

  3. Add the taxable biweekly fringe benefits (taxable life insurance, etc.) to the amount computed in step 2 to obtain the adjusted gross biweekly wages.

  4. Multiply the adjusted gross biweekly wages times 26 to obtain the annual wages.

  5. Determine the exemption allowance by applying the following guideline and subtract this amount from the annual wages to compute the taxable income.

    6. Exemption Allowance = $3,200 x Number of Exemptions

  6. Apply the taxable income computed in step 5 to the following table to determine the annual Idaho tax withholding.

    7. Tax Withholding Table
    Single

    If the Amount of
    Taxable Income Is:

    The Amount of Idaho
    Tax Withholding Should Be:


    Over:

    But Not
    Over:

    Of Excess
    Over:

    $       0
    $ 1,800
    $    0.00
    plus
    0.0%
    $        0
       1,800
       2,959
          0.00
    plus
    1.6%
        1,800
       2,959
       4,118
         19.00
    plus
    3.6%
        2,959
       4,118
       5,277
         61.00
    plus
    4.1%
        4,118
       5,277
       6,436
       109.00
    plus
    5.1%
        5,277
       6,436
       7,594
       168.00
    plus
    6.1%
        6,436
       7,594
      10,492
       239.00
    plus
    7.1%
        7,594
      10,492
      24,978
       445.00
    plus
    7.4%
      10,492
      24,978
    and over
    1,517.00
    plus
    7.8%
      24,978


    Married

    If the Amount of
    Taxable Income Is:

    The Amount of Idaho
    Tax Withholding Should Be:


    Over:

    But Not
    Over:

    Of Excess
    Over:

    $        0
    $   6,800
    $      0.00
    plus
    0.0%
    $        0
        6,800
         9,118
            0.00
    plus
    1.6%
        6,800
        9,118
       11,436
          37.00
    plus
    3.6%
        9,118
      11,436
       13,754
        120.00
    plus
    4.1%
      11,436
      13,754
       16,072
        215.00
    plus
    5.1%
      13,754
      16,072
       18,388
        333.00
    plus
    6.1%
      16,072
      18,388
       24,184
        474.00
    plus
    7.1%
      18,388
      24,184
       53,156
        886.00
    plus
    7.4%
      24,184
      53,156
      and over
      3,030.00
    plus
    7.8%
      53,156

  7. Divide the annual Idaho tax withholding by 26 and round to the nearest dollar to obtain the biweekly Idaho tax withholding.