Vietnam is preparing to enforce a law prohibiting online advertising that obscures content longer than 5 seconds.

Late last year, the Vietnamese government announced Law 342/2025/ND-CP, which outlines overall advertising regulations but includes specific provisions for online advertising, prohibiting ads that force viewers to watch them for more than 5 seconds.

Article 17 of the law regulates non-fixed ads, which are ads that obscure main content or cover the entire screen. This article requires advertising to adhere to the following requirements:

Ads must be closed in a single click; fake close buttons or buttons placed in difficult-to-close locations are prohibited.
Forced viewing of ads, whether images or videos, must not exceed 5 seconds.
A button to report illegal ads must be available.

The law was announced on December 26th and will come into effect on February 15th. The law also includes other regulations, such as the removal of illegal ads within 24 hours and the retention of online ads for review for at least 3 years.