Back taxes can be filed for up to 10 years after the tax year in which the resident neglected to file income taxes, according to ETaxes.com. After 10 years, the statute of limitations runs out for the Internal Revenue Service to collect back taxes in most states. In a few states, the statute of limitations never runs out, meaning back taxes can be filed at any point in the resident's life.
Residents who file back income taxes may be subject to late payment penalties levied by the IRS. According to TurboTax.com, residents have 3 years from the date of the missed tax filing to file taxes and claim a refund from the IRS. Otherwise the refund amount is forfeited. ETaxes.com notes that even when taxes are filed late, the IRS has 3 years from the date of the actual filing to audit the tax return. According to About.com, an amendment to a return has to be filed within the 3-year period from the original April 15th date on which taxes were due. For tax returns where the resident has requested an extension, the statute of limitations extends from the expiration of the extension date. For instance, if a resident requested an extension from the IRS that extended the tax return due date to October, then the resident has 10 years from the October date to file back taxes, rather than from the April 15th date.