Just the other day we reported Telstra’s latest stunner of a deal, 60GB for $49 per month. As we know, Optus has fired back with its own killer deal. Until June 30, you can jump on an Optus 12-month SIM plan with 100GB to burn for just $45 per month.

As is standard with Optus SIM plans, it’ll also get you unlimited standard calls and text and a handful of entertainment bonuses, like $0 subscriptions to Optus Sport and National Geographic and unmetered music streaming on Google Play, iHeartRADIO and Spotify.

Optus also includes international extras on its upper-tier SIM offerings and this particular deal will get unlimited standard international calls and text to 35 selected countries and 4GB of roaming data to use in Zone 1 countries.

100GB is more than most need on their smartphone but the Optus alternative is $40 per month for 50GB, so double the data for an extra $5 per month feels like a no-brainer.

There’s no clear winner in this battle of big data SIM only plans; we’ve always paid a premium for Telstra’s market-leading coverage and $49 for 60GB is a generous admission fee. But if you rely primarily on your mobile data and live in an area with sufficient Optus coverage, 100GB for $45 per month is hard to pass up.

Here’s a look at how these plans compare: