If you make a mistake or leave something off your return, you must correct the mistake by filing an amended return. An amended return claiming a refund of taxes already paid must be filed within three years of the original due date of the return and must be accompanied by an explanation of the claim for refund.
ON-LINE - File an amended OS-114 on the TSC/BUS. To do so, start filing the OS-114 return as if for the first time. Once you select the period, the system will recognize that an original was already filed and ask if you wish to amend the return or file a supplemental. When you choose amend, you will be brought into an editable version of the original return. Please verify that the correct amount paid with the original return is credited on line 11.
PAPER - When using a blank Form OS-114, Sales and Use Tax Return, check the amended return box (to the right of the name and address section), fill in the last date of the amended reporting period in the appropriate box and complete it using the correct figures and information for the reporting period. If you made any payment of tax with the original return, enter that amount on Line 11. Send the amended return to the address on the form.
If the amended return results in an overpayment, the Refunds, Clearance and Adjustments Unit will issue a credit and notify the taxpayer. The taxpayer may apply the credit on a future Form OS-114 or may request a cash refund. You may not take a credit for an overpayment until you have received the credit memo from the Refunds, Clearance and Adjustments Unit.