To get straight to the point, the customs agency is aware of the details of items you purchased at duty-free shops.
This is because it is clearly stipulated in the Customs Act and related public notices.
Related Laws and Regulations
According to Article 213 of the Enforcement Rule of the Customs Act, operators of bonded sales areas must record and maintain necessary information, such as sales details and purchasers' personal information, in a manner prescribed by the Commissioner of the Korea Customs Service when selling goods.
More specifically, **Article 9 (Display and Sale in Sales Areas) of the Public Notice on the Operation of Bonded Sales Areas** stipulates the following:
Operators must manage purchasers' personal information and sales details electronically immediately after selling goods, and transmit this information to the customs agency in the form of electronic documents in real time.
Furthermore, operators must record purchasers' personal information and sales details in sales ledgers or manage them electronically, and must record necessary information to allow item-by-item verification if requested by the Commissioner of the Customs Service.
As such, operators of bonded sales areas have an obligation to record purchasers' information and detailed records of purchased goods and report them to the customs agency in real time, in accordance with the law.
Therefore, information such as what items a traveler purchased at a duty-free shop and for how much is known to the customs agency.
Please be careful to faithfully declare duty-free items upon entry after international travel to avoid any disadvantages.
[This content regarding export and import clearance regulations and their interpretations is based on the customs and trade laws of the Republic of Korea.]