The Multidimensional Impacts of Hainan Island's "Customs Closure" on China's Cross-Border E-Commerce Enterprises

On December 2025, Hainan Free Trade Port officially launched full-island customs closure operations, marking a new stage in China's opening up to the outside world. The customs closure implements an innovative supervision model of "first-line liberalization, second-line control, and free flow within the island", coupled with a policy system of "zero tariff, low tax rate, and simplified tax system", exerting comprehensive and in-depth impacts on cross-border e-commerce enterprises. From four core dimensions—adjustments to tax policies, optimization of supply chain efficiency, innovation in industrial integration, and expansion of market opportunities—this paper systematically analyzes the impact mechanism of Hainan Island's customs closure on cross-border e-commerce enterprises by integrating typical cases of cross-border e-commerce enterprises and using key data such as customs clearance efficiency, cost reduction, and transaction scale. Corresponding countermeasures for enterprises are proposed to provide references for cross-border e-commerce enterprises to seize the opportunities brought by customs closure and achieve high-quality development.