You are required to file income tax return as long as you have taxable income.
You must file a tax return if your income is above a certain level. The amount varies depending on filing status, age and the type of income you receive.
For example, a married couple both under age 65 generally is not required to file until their joint income reaches $17,900. However, self-employed individuals generally must file a tax return if their net income from self employment was at least $400.
Let me know if you have any question.
Please note: This advice is provided with the understanding that all the relevant facts have been provided by you. Any change in facts might affect the advice given and hence may not be relied on in such cases. Nothing contained in this reply was intended or written to be used, can be used by any taxpayer, or may be relied upon or used by any taxpayer for the purposes of avoiding penalties that may be imposed on the taxpayer under the Internal Revenue Code of 1986, as amended.