(1) When any resident or nonresident under Article 121 (2) and (5) intends to calculate necessary expenses pursuant to Article 27 or 37 in calculating the amount of business income or other income, he/she shall obtain supporting documents concerning the disbursement of such expenses and keep them for five years from the end of the period for final return: Provided, That any person who takes a deduction for a loss which occurred five years before the starting date of each taxable period shall keep supporting documents of the taxable period in which the relevant loss occurred until May 31 of the year after the following year of the taxable period in which he/she was allowed a deduction. <Amended by Act No. 10408, Dec. 27, 2010; Act No. 11611, Jan. 1, 2013>
(2) In cases falling under paragraph (1), where any person with business income receives goods or services related to his/her business from a business entity (including a corporation) and disburses the consideration therefor, he/she shall obtain any of the following supporting documents: Provided, That this shall not apply to cases prescribed by Presidential Decree: <Amended by Act No. 11873, Jun. 7, 2013>
1. An invoice under Article 163 of this Act and Article 121 of the Corporate Tax Act;
2. A tax invoice under Article 32 of the Value-Added Tax Act;
3. Credit card sales slips under the Specialized Credit Financial Business Act (if business is conducted using a means prescribed by Presidential Decree, similar to a credit card, the supporting documents thereof shall be included);
4. A receipt (hereinafter referred to as "cash receipt") stating the details of settlement of accounts, such as the date of transactions, the amount, etc., which is issued by a device issuing cash receipts to a person who is supplied with goods or services, if a business entity who has registered as an issuer of cash receipts receives the payment in cash for his/her supplying goods or services pursuant to Article 162-3 (1).
(3) For the purpose of applying paragraph (2), in either of the following cases, a business entity shall be deemd to have discharged his or her obligations to obtain and keep the supporting documents under the same paragraph: <Amended on Dec. 31, 2022>
1. If it has issued and retains a purchaser-issued invoice under Article 163-3 due to the failure to obtain an invoice as mentioned in paragraph (2) 1;
2. If it has issued and retains a purchaser-issued tax invoice under Article 34-2 (2) of the Value-Added Tax Act due to the failure to obtain a tax invoice as mentioned in paragraph (2) 2;(4) In applying paragraphs (1) through (3), the receipt and keeping of the supporting documents on the disbursement of expenses and other necessary matters shall be prescribed by Presidential Decree.[This Article Wholly Amended by Act No. 9897, Dec. 31, 2009]