T-Mobile did not make this official, so obviously there’s catch that goes with the news. For the moment, RCS only works on the iPhone if you have iOS 18.4 Beta 2 installed, at least according to the latest reports on Reddit.
Before you start using RCS to message your Android friends, you first make sure it’s enabled by heading to Settings / Apps / Messages / RCS. Keep in mind that the RCS toggle will only appear if you have iOS 18.4 Beta 2 installed.
Unfortunately, even having RCS enabled on iOS 18.2 Beta 2 doesn’t seem to make it work for some iPhone users. That’s most likely because the implementation isn’t completed, and T-Mobile’s backend systems are only able to accept a certain number of users that probably meant to test RCS before primetime.
As an iOS developer, I downloaded the iOS 18.4 beta 2 and RCS is showing for both Light Speed and Warp, however, they are struck in “Waiting for activation”. Under the IMS in the Settings/About for both networks it shows only: Voice & SMS. RCS is not listed; it could be a bundle issue. Hopefully, with the general release of iOS 18.4, both networks RCS will work. I cannot speak for Dark Star since I don’t have it.
– reddit user highkickr, March 2025
One developer recommends a very simple solution to this “Waiting for activation” issue that some iPhone users have after enabling RCS. The solution is to simply open a conversation with a friend that has an Android phone and RCS enabled and send them a message. If the message goes through, the status should immediately change to RCS. You might also have to reboot your phone if this doesn’t work.
Sometime the RCS status only only appear after you send a message | Screenshot credit: reddit user highkickr
By the way, Google Fi users report that iPhone RCS is available for them too and so are Mint Mobile customers, but, once again, you absolutely must have iPhone 18.4 Beta 2 installed. This means that the RCS toggle will not appear on the iPhone 18 beta public.
RCS is implemented and ready to go, just make sure to activate it under Settings->Apps->Messages->RCS and toggle it on in iOS 18.4 Beta 2. Activation may take some time, there’s probably a large queue, but I do see confirmation that RCS does work in iOS 18.4 Beta 2.
– reddit user jason_he54, March 2025
