On 25th May 2025, Vietnam started blocking access to Telegram after the Vietnam Telecommunications Authority (VNTA) issued an order requiring Internet Service Providers (ISPs) to block the messaging app to limit the spread of “poisonous and bad information”. The block was lifted on 10th July 2025 on all affected networks.
This is the first time that we have seen an instant messaging app blocked in Vietnam.
The following chart aggregates OONI measurement coverage from the testing of Telegram on 12 networks in Vietnam between 27th April 2025 to 14th July 2025.
The spike in anomalous measurements after 25th May 2025 presents a strong indication of Telegram blocking, and the dates of the anomalies correlate with the timing of the government’s request to block the instant messaging app. According to OONI data, the block seems to have been lifted since 10th July 2025.
A closer look at OONI data shows that Telegram was blocked on at least 3 networks in Vietnam (FPT (AS18403), VNPT (AS45899), Viettel (AS7552)). On two of these networks (VNPT (AS45899), Viettel (AS7552)) many measurements collected after 26th May 2025 show that both Telegram web services and Telegram app endpoints were inaccessible. At the same time, OONI data shows that on the FPT (AS18403) network, the web version of Telegram remained accessible, while the application appeared to be blocked.
This is further suggested by OONI measurements pertaining to the testing of telegram.org
, collected between 26th May 2025 to 10th July 2025 in Vietnam. Telegram’s main domain was blocked on the VNPT (AS45899) and Viettel (AS7552) networks, but it remained accessible for FPT (AS18403) users.
Overall, OONI data shows strong signs of Telegram blocking on at least three networks in Vietnam. However, it’s worth noting that OONI data shows that Telegram remained accessible on at least one network in Vietnam between 26th May 2025 to 10th July 2025.
If you are in Vietnam, you can help test Telegram and contribute more measurements by running OONI Probe.