The most common reason a customer with a 5G-capable prepaid plan sees 3G-era speeds is the phone. Networks publish coverage and caps; the device decides whether any of it is available to you.
The published requirement
The Boost Critical Information Summary states that you need to have an LTE band 3 (1800MHz) and band 28 (700MHz) capable device. Those are the bands this network uses, and a device that lacks them cannot use it, regardless of what the plan includes.
What happens on an incompatible device
The summary is unusually direct about the consequence: it may be blocked and may not have access to voice or data, or be able to call emergency services including triple zero. That last clause is the one to take seriously. An incompatible device is not merely slow, it may not work, and the emergency services clause means this is a safety issue rather than an inconvenience.
How to check your own phone
- Look up your model in the manufacturers specifications for 4G LTE band 3 and band 28 support.
- A phone sold in Australia for the last several years generally has both; a very old or very cheap imported device may not.
- If you are unsure, the safe test is whether the plan activates and whether 4G appears in the network indicator on the status bar.
We do not publish a phone compatibility list, because it would go stale and the cost of being wrong is a customer who cannot call for help. The two band numbers are the check, and they are published by the provider.
What we could not verify. Where a provider has not published a figure we mark it unknown rather than estimate it. Re-read the provider page linked below on the day you decide.