Utah considers all income earned in the state as taxable income. This will include any wages and tips you receive as an employee or, if you are self-employed, the amount of your gross earnings minus any applicable business expenses. Certain unearned income is also taxable, such as unemployment compensation and retirement benefits.http://tax.utah.gov/forms/current/tc-40inst.pdf  

But even if you earn money during the year, you will only be required to file a state tax return if your adjusted gross income, or AGI, is greater than the amount of your standard deduction and exemptions. For complete information regarding filing requirements, visit the Utah State Tax Commission website. The filing deadline for the 2010 Utah return is April 18, 2011.http://tax.utah.gov/forms/current/tc-40inst.pdf 

Before beginning work on your Utah tax return, you should collect all of the relevant tax information and paperwork you will need to complete the tax form. This will include the documents that relate to personal identification and your earned income for the tax year:

1. Your full name and Social Security number
2. Your current mailing address
3. Your spouse's name and Social Security number, if you are filing a joint tax return
4. The total amount of your state taxes paid during the year - If you are an employee, this will be shown on your Form W-2 as state taxes withheld. If you are self-employed, this will be the amount of any estimated tax payments you made during the year.
5. A copy of your federal income tax return, if you are filing one
6. Documentation of your earned income for the year - If you are employed, this will be either a Form W-2 or a Form 1099. If you are self-employed, you will need to total your earnings yourself.
7. Documentation of any qualified business expenses you incurred
8. Documentation of any unearned income received during the year that is taxable by the state of Utah - This includes unemployment benefits, retirement payments, interest and dividends, rental income, etc.http://tax.utah.gov/forms/current/tc-40inst.pdf 
   

If you will be filing a federal tax return, you should do so before beginning your Utah forms because you will be using your federal adjusted gross income, or AGI, to begin your state return. If you are not required to file a federal return but you are still filing a state return, you may want to consult a tax professional to help you figure your AGI.http://www.irs.gov/pub/irs-pdf/f1040.pdf

Now that you have all of the information you will need, you can start on your Utah tax return. If you have access to the Internet, you can download Form TC-40 "Utah Individual Income Tax Return" as well as the Form TC-40 Instructions from the Utah State Tax Commission website. You can then print the form out and complete it by hand or use the fill-in form to complete it on your computer.http://tax.utah.gov/forms/current/tc-40inst.pdf  

If you do not have access to the Internet, you can usually pick up a copy of the form and instructions at your local library. If you prefer to file your return electronically, you can do so by completing the form online through the Tax Express portal on the State Tax Commission website.http://taxexpress.utah.gov/ 

Should you decide to file your federal return by using tax preparation software or a tax preparation website, you can usually add on your state form for an additional fee. The information you need to file the state return is automatically imported from your federal return for easy filing.http://tax.utah.gov/mef/  

To begin your Utah tax return, enter your Social Security number and full name. Then enter your spouse's Social Security number and name, if applicable. Complete the address section, select your filing status and number of exemptions. Then stop to read the form instructions. The instructions explain various state credits and deductions for which you may qualify.http://tax.utah.gov/forms/current/tc-40.pdf 

Once you have finished reading the form instructions, you can finish your tax return. Begin by entering your federal AGI on line 4 of your Utah return. Your federal AGI will be listed near the bottom of page one on your IRS Form 1040. From there, you will need to consult the Utah tax instructions as you complete each additional line. This will help you to see what income adjustments you will add and what credits you will be able to deduct.http://tax.utah.gov/forms/current/tc-40inst.pdf 

Continue working through the return until you reach line 21. Here you will calculate your Utah income tax liability. Since Utah has a flat tax rate, this will be fairly simple. After you figure your tax, subtract any additional credits to see your total tax on line 31.http://tax.utah.gov/forms/current/tc-40.pdf 

Then you will subtract your state tax withholding and any estimated tax payments you have remitted. This will leave you with either the amount you overpaid (refund) or the amount you underpaid (balance due).http://tax.utah.gov/forms/current/tc-40.pdf

If you are due a refund, select whether you would like your refund issued as a check or via direct deposit. Then sign and date the return and, if you are filing jointly with your spouse, he or she needs to do the same. Make a copy of the form for your records.http://tax.utah.gov/forms/current/tc-40.pdf 

To file by mail, send the original return to the address listed in the tax form instructions. If you have a balance due, send a check or money order for the total owed along with your return. Be sure to send it off by April 18, 2011, to avoid a late filing penalty.http://tax.utah.gov/forms/current/tc-40inst.pdf

To file electronically using the Tax Express website, simply follow the screen prompts. To file electronically using tax preparation software, follow the directions in the program to submit your return.http://taxexpress.utah.gov/income.html