Telstra will be implementing a 20 per cent price rise for prepaid mobile services from the start of July.

The telco told customers the change was necessary to allow continued investment in Telstra’s “mobile network, products and services”.

A $10 prepaid card will now cost $12, the $30 tier is now $35, $40 likewise jumps to $45, and $60 worth of credit will now be priced at $65.

All the tiers have has the data allowance increased, but the decision is unlikely to be popular with customers.

Telstra acknowledged in its letter to customers that “any price rise is hard” and “a range of factors” has resulted in the increase.

“Maintaining both the affordability of our services and our ability to continue investing is a tough balancing act, and one that we feel the weight of given how important connectivity is,” a company spokesman said.

Last June, Telstra increased its post-paid pricing by between 4 and 5 per cent, and introduced an annual pricing review, which would be pegged to the consumer price index.

This suggests another hike for those post-paid plans will come shortly.