Vodafone Australia is starting to re-farm metropolitan 2100 MHz spectrum currently used for 3G services to its 4G network.

Spectrum reallocation has already started in the Australian Capital Territory, and work is set to start in NSW from March 18.

Vodafone said in a statement that “Victoria, Queensland, Western Australia and South Australia [are] to follow throughout 2019.”

The telco said the reallocation would bring “improved 4G services and capacity to more than two million local customers.”

Access delivery networks general manager Tom Joynson said the change was needed to keep pace with 4G growth and data usage.

“More than 90 percent of our mobile customers use the 4G network with 4G data usage across our network increasing by 58 percent during 2018,” he said.

“Once the upgrade work is complete in each state, we will be delivering even better service to more than 90 percent of Vodafone’s mobile subscribers across Australian metro areas.”

Vodafone said that once the upgrades were finished, however, that some customers using handsets compatible only with 3G 2100 MHz spectrum would need to upgrade.

“A small number of older mobile devices that are only compatible with 3G 2100MHz spectrum won’t work when the spectrum becomes part of the 4G network,” the telco said.

“We encourage those customers to get in touch with us before the work begins to ensure there is no interruption to their service.”

Other telcos are performing similar reallocations.

Telstra will shut off 3G services operating in the 2100 MHz band on March 25.

“Only a tiny proportion of Telstra’s mobile traffic is currently using the 2100 MHz spectrum, which has always been a supporting capacity layer,” Telstra said last year.

“Over time, we have seen more and more customers using Telstra’s 4GX service to ensure greater coverage, network reliability and consistently fast speeds.

“By re-purposing the 2100 MHz spectrum from 3G to 4GX, Telstra is increasing capacity to where there is greater customer demand.”

Vodafone still runs 3G services for metro and regional areas in the 900 MHz. Telstra also runs 3G services in 850 MHz spectrum.