Income Limits

• If your income is below the limit set by the Internal Revenue Service for your age and filing status, it is not necessary to file an income tax return. These income limits range in 2010 from $3,650 if you are married and file separate returns, to $20,900 if you are a married couple over age 65 and filing a joint tax return. The income limits have key exceptions; for example, if you did not live with your spouse at the end of 2010, or on the date your spouse passed away if it was during 2010, you are required to file a tax return if your income was at least $3,650 no matter how old you were. Typically, Social Security income does not count toward the income limit, unless you are marred, live with your spouse, but file under the "married filing separately" status.
  
  

Exceptions to Income Limits

• Income limits for filing an income tax return have another notable exception. If you are self-employed, or make more than $400 in a year from self-employment income, the Internal Revenue Service expects you to file a tax return. It is also necessary to file a tax return if you sell your home. You are also required to file a tax return if you owe Social Security and Medicare taxes on tips, failed to take the required minimum distribution from your retirement plan and you were over 70 1/2.
  
  

Tax Credits

• If you are entitled to the Earned Income Tax Credit (EIC), Additional Child Tax Credit or had federal income tax withheld that can be refunded to you, you will need to file a tax return to claim these credits. Other temporary tax credits may be offered, like the Making Work Pay or First-Time Homebuyer tax credit, that also require you to file a tax return to claim the credit.
  
  

Ask an Accountant

• If you are uncertain about whether you are eligible to claim a tax credit or need to count money that you received during the year as income, ask a certified public accountant. He will be aware of the current tax regulations, income limits and filing requirements.