- The IRS usually automatically corrects typical calculation errors. However, an amended return is filed to make changes to a taxpayer's deductions, exemptions, credits or income. For example, if you added on a credit that you weren't entitled to or omitted a deduction that you were eligible for, you should file an amended return to make the correction.
- If your amended return results in you owing tax, interest penalties will be assessed on the tax owed if the amount due is not paid within 21 days of the demand for payment notice. The failure to pay the penalty is ½ of 1 percent of the unpaid tax for each month, or part of the month, that it remains unpaid or until the maximum amount of 25 percent is reached. You may also be assessed penalties if you substantially understate the tax on your original return, were negligent or were found guilty of tax fraud. Interest is charged from the due date of the return and is determined quarterly at 3 percent plus the federal rate.
- Taxpayers who do not owe tax are not charged penalties and interest if they file an amended return. Interest is usually paid on your refund.
- Penalties can be removed if the taxpayer did not meet his tax obligation due to a reasonable cause. Examples of a reasonable cause include, but are not limited to, illness, incarceration, oversees travel and military service. To request that your penalties be removed, complete IRS form 843 and mail it to your servicing center. On the form, indicate the tax year for which you're requesting the removal of penalty, the type of tax (usually income), original 1040 return and a written explanation of the events that lead to the circumstance. Although form 843 does allow you to claim a removal of interest, interest abatements are far less likely than penalty abatements and are based on different criteria. Reasonable cause is not an acceptable reason for an interest abatement. Examples of acceptable reasons for interest removals include unreasonable IRS delays and erroneous IRS interest assessments.