Unfortunately it appears that ad-free streaming for Prime members has come to an end, according to an update on the Twitch blog. According to the post, “As we have continued to add value to Twitch Prime, we have also re-evaluated some of the existing Twitch Prime benefits. As a result, universal ad-free viewing will no longer be part of Twitch Prime for new members, starting on September 14.”
For those who are Twitch Prime subscribers doing a month-to-month subscription, ad-free viewing will still be available until the 15th of October. For those who are on annual subscriptions or upgrade to an annual subscription before the 14th of September, you will continue to enjoy ad-free streaming until the next subscription renewal date.
If ad-free streaming is something that you really want, Twitch points users towards the Twitch Turbo plan which will continue to allow users to enjoy ad-free streams (for a price, of course) at $8.99 a month.