DMR Tier III (or DMR Tier 3) radios operate in the same frequency range as Tier II radios, but have the added advantage of allowing all sorts of extra features to customize the system to your situation.

DMR Tier III radios operate in the so-called ''Trunked Mode''. This means that the radios are automatically assigned to specific frequencies instead of operating on a fixed frequency.

Trunking allows you to license fewer frequencies to establish the same amount of communication. Automatic frequency assignment prevents two groups from trying to communicate on the same frequency. This is increasingly important in larger systems.

DMR Tier III also adds additional data capabilities that allow radios to use SMS messaging, location services (GPS), telemetry data, remote programming and remote control. Even radios that have been forgotten to turn off can be turned off remotely.

See BelFone radio trunking system based on DMR Tier III open standard: Basic-built Trunking System(BTX), Enhanced Trunking System(ETX)