South Korea has suddenly launched strict inspections of e-cigarettes from China, extending its scrutiny even to supply chain documentation.

In its recent crackdown on e-cigarettes, South Korea is no longer merely checking "whether the products contain nicotine"; instead, it is now extending its investigations upstream along the supply chain.

On September 23, South Korea's Customs Agency announced new customs clearance management measures for e-cigarette liquids: effective from August 18, all imports of "nicotine-like" and nicotine-free e-cigarette liquids will undergo documentary review; meanwhile, all import declarations for e-cigarette liquids must undergo compositional analysis prior to customs clearance.

What deserves particular attention from China's supply chain is that South Korean customs have explicitly stated that, given the fact that the majority of such products originate from China, they are currently examining the trade chains within China—from production and distribution to export—and verifying the authenticity of relevant documentation.

This signifies a shift: South Korea is no longer merely investigating "what Chinese e-cigarettes are," but rather "where Chinese e-cigarettes come from."

Why has South Korea suddenly turned its attention to China's supply chain?

One very direct reason is that the vast majority of e-liquid products imported by South Korea originate from China. According to data from the Korea Customs Service, from January 1 to September 20,2026, South Korea imported approximately 15 tons of nicotine-containing e-liquids, of which 99.99% came from China; during the same period, it imported approximately 316 tons of nicotine-free e-liquids, of which 99.7% came from China.

Consequently, South Korean customs do not face an ordinary import goods market. When a large volume of products originates from the same source, regulatory oversight naturally extends its focus further upstream.

However, there is an even more significant background to this situation: on April 24,2026, South Korea will incorporate synthetic nicotine into its tobacco regulation and taxation framework.

In the past, certain e-liquid products may have entered South Korea under categories such as "nicotine-free" or "nicotine-like." Now that synthetic nicotine has also come under tax jurisdiction, a key area of focus for South Korean customs authorities has become preventing products that should be subject to taxation from being declared as products exempt from such taxes.

This also constitutes the core rationale behind this operation.

What exactly is South Korea investigating this time?

The most significant change is that the document requirements have increased markedly.

Starting from June 15,2026, South Korea will require imported nicotine-containing and nicotine-free liquid products to submit an MSDS (Material Safety Data Sheet) that confirms the presence or absence of nicotine. From August 18, all relevant products will undergo comprehensive document review.

When filing import declarations, the following five categories of documents must be submitted: MSDS; electronic transaction-specific contract; transaction relationship diagram among overseas manufacturers, distributors, and exporters; China export declaration documents; and production license certificates.

Moreover, Korean customs not only require the submission of documents but also verify their authenticity.

This change warrants close attention from China's supply chain sector. In the past, many enterprises understood "compliance" primarily as meeting product composition requirements. Now, South Korea requires further clarification: Who produced the product? Who sold it to whom? Who exported it? Does China have corresponding export declarations? Does the manufacturing enterprise hold the requisite permits?

In other words, product compliance is evolving into supply chain compliance.

A tougher move: South Korea has adopted a "inspect goods first, then release" approach.

South Korean customs have also revised its composition testing methodology. In the past, imported e-liquid products were primarily subject to sampling-based testing. Starting from July 16,2026, the Korea Customs Service's central analysis agency will conduct pre-clearance composition analysis on all imported e-liquid declarations.

Furthermore, South Korea has collaborated with its food and drug safety authorities to establish a unified analytical method for novel "nicotine-like" substances, which has been implemented across all national customs checkpoints since July 28.

In the past, the process might have been: filing → spot checks → release. Currently, it has evolved closer to: filing → document review → component testing → supply chain verification → further determination of release.

For Chinese enterprises operating in the Korean market, the most significant change is not simply "stricter inspections," but rather that customs clearance is increasingly resembling a comprehensive supply chain audit.

Why is South Korea so particular about details?

The Korea Customs Service has reported that from 2022 to September 2026, multiple cases have been identified in which nicotine-containing e-cigarette liquids were misdeclared as nicotine-free products. In the period from 2025 to September 2026 alone, 22 such cases were detected. The Korea Customs Service has also found that some companies may circumvent tax and regulatory requirements by altering the declared product category of their goods.

Consequently, this time South Korea did not target a single brand or a specific product; instead, it took a comprehensive approach by examining the entire import supply chain. Every entity—from manufacturing enterprises to traders, and further to exporters and importers—was included within the scope of the verification process.

This is also why this development is of greater significance to China's supply chain than the mere news that "South Korea has tightened e-cigarette regulations."

For Chinese factories, the biggest problem may not be the products themselves, but rather "mismatched documentation."

This may be the most significant warning that South Korea's recent policy has sent to China's supply chain.

Suppose a Chinese factory produces e-liquid. The product itself is in good condition, but if the following occurs:

· The MSDS does not match the actual composition;

· The export declaration information of China is inconsistent with the import declaration information of South Korea;

· The relationships among manufacturers, traders, and exporters are unclear;

· The production permit documents are incomplete;

· The actual flow of goods is inconsistent with the declared transaction records.

In such cases, the question is no longer simply "can the product pass inspection?" but rather "can the entire supply chain be proven authentic?" This would directly increase the transaction costs for companies entering the Korean market.

China's e-cigarette exports are entering an era of "supply chain transparency".

It should be emphasized that the measures taken by South Korea's Customs Agency this time target the import of nicotine-and nicotine-free e-cigarette liquids, and should not be simply interpreted as "South Korea is conducting comprehensive strict inspections of all Chinese e-cigarette brands."

However, given that the relevant imported products are highly concentrated in China, the impact on China's supply chain will be even more direct. In the future, Chinese enterprises expanding into overseas markets may need to prepare two sets of preparations: one set consists of the products themselves; the other set consists of a complete chain of evidence demonstrating why these products comply with relevant regulations.

These documents, which were once easily regarded as "trade-related documents," are now becoming an integral part of a product's entry into overseas markets.

SONG VAPE has consistently adhered to a global market compliance strategy, continuously investing in product quality control, comprehensive supply chain documentation, and a complete set of export filing systems, thereby helping its global partners mitigate customs clearance risks arising from changes in international trade regulations. In the second phase of global expansion for overseas e-cigarette businesses, a compliant supply chain has become the core competitive advantage.

Therefore, the signal South Korea has truly sent this time is not: "South Korea has once again tightened its regulations on e-cigarettes," but rather: "The overseas market is increasingly beginning to rigorously scrutinize the supply chain behind Chinese e-cigarettes."

For Chinese e-cigarette companies, the key competitive advantage in their next phase of global expansion will be their ability to integrate products, regulatory documentation, trade operations, and supply chains into a cohesive system that can withstand rigorous scrutiny. This may emerge as the new threshold for competition in China's e-cigarette overseas expansion.