Revised Invoice

You cannot edit, cancel, delete, or dispose of e-Tax invoice that is already filed to the National Tax Service. If you need an amendment for correcting any mistakes on the entries, you must issue a proper revised invoice. You can only write this type of invoice when the status of the original invoice is ‘Succeeded’, whereas you must create a new tax invoice when the status is ‘Failed’.

Reasons	Correction of Errors	Changes in Supply Cost	Return	Cancellation of Contract	Post Opening of Local L/C	Duplicated Issuance
Code	1	2	3	4	5	6

The revised invoice uses the identical [Registlssue – issue an e-Tax invoice] API used for issuing a general tax invoices, and you must additionally include the modification code(modifyCode) and the NTS confirmation number of the original invoice(orgNTSConfirmNum).

※ It is not mandatory to implement all the functions listed in this guide. To reduce the development time, you can select the desired functions required for your work.

Correction of Errors

This reason of amendment indicates when ‘requisite entries’ (information that directly affects the effectiveness of a tax invoice), and ‘optional entries’ need corrections due to a mistake, cause other than mistake, or applied the wrong tax rate to issue a tax invoice.

How to Write	Cancelled Copy: issue a negative(-) e-Tax invoice that contains identical information as the original one. Modified Copy: issue a positive(+) e-Tax invoice that contains the revised information. ※ In addition to the original copy, you are issuing two other copies. Example) - Original Copy +550,000 reported - negative(-) invoice (Credit note worth of -550,000) - positive(+) invoice (Debit note worth +600,000) Issue 2 Copies
Date of Preparation	Cancelled Copy : date of preparation described in the original e-tax invoice Modified Copy: date of preparation described in the original e-tax invoice or the date you make an amendment. You may be subjected to penalty taxes, if the date of preparation is set in the future date than the original date of issuance.
Due Date	When you notice the error (no restriction on the date) An exception occurs when a cause is other than a mistake, which you must issue a revised e-invoice by the deadline for a final return.
Caution	Taxation Type (Tax/Zero-rated ↔ Tax Exemption) modification is not allowed for correction of errors reason.

Glossary

Requisite Entry Items: Seller(registration number, name of the owner, company name), Buyer(registration number), date of preparation, supply cost, tax amount
Optional Entry Items: All the other entry items other than requisite entry items (e.g., address, type of industry, type of business , type of item, contact for PIC, email etc.)

Changes in Supply Cost

This reason of amendment indicates instances of an increase or decrease in supply value. Make sure to include the amount of difference(increased/decreased) from the original supply value.

How to Write	Increase: issue a positive(+) tax invoice that contains the increased part of the total amount stated in the original e-Tax invoice. Decrease : issue a negative(-) tax invoice that contains the decreased part of the total amount stated in the original e-Tax invoice. ※ Supply cost on the original e-Tax invoice + supply cost(+/-) on the revised invoice = final supply value Issue 1 Copy
Date of Preparation	The date of the occurrence of changes in supply cost - write “the date of preparation on the original tax invoice” on the remark of the revised invoice
Due Date	The 10th day of the following month of the date of occurrence of changes
Caution	You can only deduct(-) the total amount of the original e-Tax invoice through the following reasons: “cancellation of contract” or “duplicated issuance”, other than “changes in supply cost”.

Return

This reason of amendment indicates when the initially supplied item is partially returned.

How to Write	Issue a negative(-) tax invoice that contains the returned amount of the total amount. Issue 1 Copy
Date of Preparation	The returned date └ write “the date of preparation on the original tax invoice” on the remark of the revised invoice
Due Date	The 10th day of the following month of the date of occurrence of return
Caution	If there is a cancellation of the contract on the service, select the “cancellation of contract” for a reason for amendment, other than “return”.

Cancellation of Contract

This reason of amendment indicates instances such as cancellation of contract, service and product is not supplied.

How to Write	Issue a negative(-) tax invoice that contains the returned amount of the total amount. Issue 1 Copy
Date of Preparation	The date of cancellation of a contract └ write “the date of preparation on the original tax invoice” on the remark of the revised invoice
Due Date	The 10th day of the following month of the date of occurrence of changes
Caution	According to the [Amendments to the Enforcement Decree of the VAT Act on July 1st, 2012], you must use the actual date when the cancellation of contract occurred for "the date of preparation" on the revised invoice.

Post Opening of Local L/C

This reason of amendment indicates when a local L/C is established or a confirmation of purchase is issued after the deadline of the taxable period(1/1~6/30 or 7/1~12/31), which the time of supply of the item or service is included, or within the 25th day of the following month(July or January).

How to Write	Cancelled Copy: issue a negative(-) tax invoice regarding the items of the established local L/C Modified Copy: issue a zero-rated, positive(+) tax invoice regarding the items of the established local L/C ※ API system does not automatically assign the taxable type. Make sure to manually assign negative(-) as taxable invoice and positive(-) as zero-rated invoice. Issue 2 Copies
Date of Preparation	Write the date of preparation on the original tax invoice └ Write “the establishment date on the remark of the revised invoice
Due Date	If the opening date is included within the taxable period: issue until the 10th day of the following month of the establishment date. If the opening date is included after the taxable period ends: issue on the 25th day of the following month of the deadline of the taxable period
Caution	When it is established or confirmation of purchase is issued after the taxable period ends, you can only apply zero tax rate for the revised invoice that is issued until the 25th day of the following month of the deadline of the taxable period.

Duplicated Issuance

This reason of amendment indicates when you issue two or more copies of e-Tax invoices regarding the single transaction by a simple mistake, or when you issue a e-Tax invoice that contains the wrong taxation type(tax/zero-rated ↔ tax exemption).

How to Write	Issue a negative(-) tax invoice that contains identical information as the original e-Tax invoice Issue 1 Copy
Date of Preparation	The date of preparation on the original e-tax invoice
Due Date	The day that you recognize the mistake (no restriction on the date)
Caution	You may be subjected to vocation of a tax officer of the National Tax Service, if you issue a revised invoice using “issuance of duplicates” selection for the customer with no previous transaction history.