Satellite SMS will allow you to send a text message in areas without a 4/5G or Wi-Fi connection. It is primarily for emergency messages and only works on selected phones.
It goes under a few names: Satellite SOS, Direct to Device (D2D), Satellite to Mobile (STM), Direct to Handset (DTH), or Direct to Cell (DTC). To be clear, it will not support voice, images, attached files, or rich text. Currently, Telstra, Optus, and Vodafone only have proof-of-concept trials. Test results are confidential, but informed sources say that due to lag (several hundred milliseconds), SMS is all that it will handle.
The SMS is transmitted directly to the satellite, which then relays it to a ground station, where it enters the standard Telco SMS network. Message recipients only require a standard handset.
Compatible Hardware
Once the service is tested and running, you will see more satellite SMS compatible phones. Some existing ones will need a firmware update.
Despite some rumours that any 4/5G phone will work via an app, at this stage, only the following have the right hardware.
- iPhone 14 and later running iOS 18.X.X
- Samsung Galaxy S25-series, Android 15, with Qualcomm SD 8 Elite processor
- Google Pixel 9 series (note that this is different to the Google Satellite service in the USA)
When can I use it?
Unlikely before the end of 2025.
Satellite SMS is a last resort, emergency messaging service when there is no 4/5G or internet-connected Wi-Fi service.
It must be used outside with a clear view from the horizon to the sky. It is an intermittent service, meaning there will be periods when service won’t be available as no satellite is in range.
Satellite SMS will be a boon to bushwalkers, campers, and others in areas without 4/5G network coverage. However, it won’t replace 4/5G for voice and data.
Satellite SMS providers
Telstra will reserve the service for its direct retail customers. It is using SpaceX satellites and has no plans to roll it out to its MVNO wholesale resellers.
Optus is also using SpaceX satellites on the 2600MHz band and has not announced a launch date. It is not planning to make it available to MVNOs.
Vodafone (TPG Telecom) has successfully sent the first direct-to-smartphone text message on the Vodafone mobile network using Lynk Global’s fleet of low-earth-orbit satellites.
Cost
No Telco has advised costs or availability. As it is limited to SMS, the cost is likely to be per message/kilobyte.
Garmin operate SMS messaging on the Iridium Satellite Network and has subscription costs ranging from $25 to $85 per month with free 000 messages and $0.85 per SMS.
Comments