Microsoft hasn't communicated any official number for Game Pass subscribers since last year when it was officially revealed that it had reached over 25 million users. Since then, members from the Xbox team (including the Xbox boss Phil Spencer) has said that the number has increased, but without sharing how much.
Earlier today, we got a hint though from Xbox marketing exec Craig McNary, who wrote on his LinkedIn that Game Pass had surpassed 30 million users last month (August): "Launched and grew Xbox Game Pass, the world's #1 gaming subscription service, to over 30M members". This was noticed by Tumur222 on X who screengrabbed the evidence. When this was shared on social media, McNary silently decided to remove this number as it seemingly wasn't meant to be public information.
As an Xbox exec, McNary had the correct information available, so it seems fairly plausible that this is correct information on the number of subscribers. As Xbox Game Pass Core launched earlier this week, it is believed that the number of Game Pass subscribers will increase by a lot this month as all Xbox Live Gold subscriptions are automatically converted to Core. Hopefully this means Microsoft will be inclined to provide an official update on the current number of Game Pass subscribers.
Thanks, Pure Xbox.