TAXES 18-51, Colorado State Income Tax Withholding

Published: May 14, 2018
Effective: Pay Period 09, 2018


The annual allowance amount, per exemption claimed, has changed for the State of Colorado. No action on the part of the employee or the personnel office is necessary.

Tax Formula

State Abbreviation:


State Tax Withholding State Code:


Acceptable Exemption Form:


Basis for Withholding:

Federal Exemptions

Acceptable Exemption Data:


TSP Deferred:


Special Coding:


Additional Information:

A State tax certificate is not required since Federal exemptions are used in the computation of the State formula.


Withholding Formula (Effective Pay Period 09, 2018)

  1. Subtract the nontaxable biweekly Thrift Savings Plan (TSP) contribution from the gross biweekly wages.
  2. 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.
  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 by the number of pay dates in the tax year to obtain the gross annual wages.
  5. Determine the exemption allowance by applying the following guideline and subtract this amount from the gross annual wages to compute the taxable income:

    Number of Exemptions

    Exempt Amount





















    10 or more



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

    Single Tax Withholding Table

    Taxable Wages

    Amount of Tax

    Over $0 but not over $2,300


    Over $2,300

    4.63% of excess over $2,300

    Married Tax Withholding Table

    Taxable Wages

    Amount of Tax

    Over $0 but not over $8,650


    Over $8,650

    4.63% of excess over $8,650


  7. Divide the annual Colorado 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 Colorado tax withholding.
  8. Add any 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 this pay period.


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) homepage. Select the Publications tab and select U.S. Income Tax Formulas from the Publications menu to launch the tax map. Select the desired State from the map provided for the formula.

Previous Tax Bulletin


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