What Form 843 Does
Form 843 is an official IRS form that allows individuals and businesses to request money back from the government or ask for relief from penalties and interest charges. You might file this form if you paid taxes that you believe were incorrect, if you overpaid your taxes, or if you want the IRS to remove penalties or interest that were added to your account.
Common Reasons to File
Taxpayers file Form 843 for several reasons including overpayment of federal income tax, estate tax, excise tax, or employment taxes. It can also be used to request that the IRS remove penalties for late filing or late payment, remove interest charges, or correct errors made by the IRS on a tax account. Some people file it to claim refunds for taxes paid on income that was later determined to be non-taxable.
Time Limits for Filing
There are strict deadlines for filing Form 843. Generally, you must file within three years after you filed your original tax return or within two years after you paid the tax, whichever date is later. If you do not file within these time periods, you may lose your right to a refund. There are some exceptions to these rules in special circumstances.
What Information You Need
When completing Form 843, you will need to provide your tax identification number, the tax year in question, the type of tax involved, the amount of the claim, and a detailed explanation of why you believe you are entitled to a refund or relief. You should include copies of supporting documents such as receipts, cancelled checks, or correspondence with the IRS.
After You File
After submitting Form 843, the IRS will review your claim and supporting documentation. This process can take several months. The IRS will notify you in writing of their decision to approve, partially approve, or deny your claim. If you disagree with the IRS decision, you may have the right to appeal. 
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