How many TVs can simultaneously use a single YouTube TV account?

As of the latest available information, a single YouTube TV account can be utilized across multiple devices, but when it comes to simultaneous streaming, there's a limit. A YouTube TV subscription allows for three separate streams at the same time. This means that while one can log into the same account on different televisions or devices such as smartphones, tablets, and computers, only three of those devices are able to stream content through YouTube TV concurrently. This design is intended to accommodate households with multiple viewers without allowing unrestricted sharing of the service outside of the subscriber's household.