If you are an Ohio resident or if you earn money in the state of Ohio, then your income is subject to tax by the Ohio Department of Taxation. Learning how to prepare your own state tax return will help you to take advantage of available deductions and credits to reduce your tax.http://www.tax.ohio.gov/ NOTE: The Ohio filing deadline has been extended to April 18 for the 2010 calendar year.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf 

For employees, most forms of earned income are taxable, including wages, tips, salaries and commissions. For self-employed taxpayers, the taxable income includes gross earnings minus any applicable business expenses. Other forms of income are also taxable, including gambling winnings, unemployment compensation, retirement distributions, and interest and dividends, among others. Before you begin preparing a return, however, check the filing requirements. You may not have to submit a return if you make less than the income threshold set for tax.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf 

To prepare your Ohio state tax return, the first thing you need to do is look over all of your essential tax paperwork. You will want to gather this together before you begin to save time once you start working on the return. The information you need will include the following: 

1. Your Social Security number
2. Your current mailing address
3. Your date of birth
4. Your spouse's full name, date of birth and Social Security number, if you will be filing a joint tax return
5. Your total earned income for the year, including any wages from a Form W-2 or Form 1099––If you are self-employed, use your gross earnings minus qualified business expenses.
6. Your total unearned income that is subject to taxation, such as unemployment benefits, rental property income, or bank dividends
7. The amount of your state income tax payments––If you are employed, this will be the amount shown on your Form W-2 as state tax withheld. If you work for yourself, this will be the total of any estimated tax payments you made during the year.
8. A copy of your federal income tax return, if you are filing one 
   

If you will be filing a federal tax return, complete that form before you begin your Ohio return. You will be using your federal adjusted gross income, or AGI, to begin your Ohio tax form.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_2010_SFI.pdf  If you are not filing a federal return, you may want to consult with a tax professional who can help you to calculate this figure. 

To save processing time, consider filing your Ohio return electronically. You can do this yourself by filing through the Ohio Department of Taxation website. It is available at no charge and you can access it anytime.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf 

Now that you have your necessary tax information, you need to get a copy of your Ohio tax return. If you have Internet access, you can download the Form IT-1040 "Ohio Individual Income Tax Return" and the accompanying instruction booklet from the Department of Taxation website. If you prefer, you can fill in the form on your computer. To complete the form by hand, simply print it out. If you do not have access to the Internet, you can generally pick up a paper copy at your local public library.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_2010_SFI.pdf 

The state of Ohio also has a simplified tax return called the Form IT-1040 EZ "Ohio Individual Income Tax Return for Full Year Residents".http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_2010_SFI.pdf  This form can be used by many Ohio residents as long as they are not claiming certain credits and they meet tests regarding income and residency status. All Ohio residents qualify to file using the standard tax form, IT-1040.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf 

If you are filing by hand, be sure to write clearly and use black ink. This will help you to avoid any processing delays. Begin the form by entering your name, date of birth and Social Security number, as well as your spouse's if necessary. Complete the address section, then select the appropriate residency status. Choose the filing status that corresponds with the filing status you used on your federal tax return.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_2010_SFI.pdf 

Before you go any further, stop and read the Ohio IT-1040 instructions to learn about the state income adjustments you may need to make and the state credits you may be eligible to claim. Once you begin the form, stop and consult the instructions anytime that you need clarification.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf 

Start by entering the amount of your federal adjusted gross income. The Ohio form will direct you where to find this amount on your IRS Form 1040. Then you will make any necessary state income adjustments. After subtracting or adding these, you will arrive at your Ohio adjusted gross income. Once you subtract your state exemptions, you will be left with your Ohio taxable income.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf 

Next, you will need to consult the tax tables located in the form instructions to assess the tax owed on your income. Locate your appropriate income bracket and enter the amount of tax shown. From here, you will work through the remainder of the form subtracting eligible state credits that you can claim.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf 

You will also subtract the amount of your state income taxes paid during the year. Afterward, you will have either an overpayment or an underpayment of tax. An overpayment entitles you to a refund. An underpayment will require you to pay additional tax.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf 

Sign and date the return. Have your spouse do the same. Then make a copy of the completed form for your records. If you are filing by mail, enclose the return along with a check or money order for any taxes owed in an envelope. Send the return to the address stated in the form instructions.http://tax.ohio.gov/documents/forms/ohio_individual/individual/2010/PIT_IT1040_Instructions.pdf

If you are filing electronically and you have a balance due, you will be given the option of paying your taxes with a credit or debit card. Whatever method you choose to use, be sure to submit your return by April 18. Should you need additional time to prepare your return, you may want to find out how to get a state tax extension in Ohio.