Best SIM-only plans in Australia (August 2025) | Compare the 7 top plans

There is a flexibility benefit to going SIM-only with your phone plan. Going SIM-only allows you to save money on a month-to-month basis,cuts off your ties to a lengthy contract and may be your option of choice if you want to continue to use your current phone. Give it some thought if you want to consider a cheaper MVNO that doesn’t offer phones on a plan, too.

Using an eSIM cuts out the need to remove and reinsert the SIM card tray in your smartphone, effectively minimising what is often a headache when getting a new phone. eSIMs are basically virtual SIM cards that operate within your phone – no card required – but your phone will need the functionality and your plan will need to offer eSIM access as an inclusion. Check with your telco if you can get an eSIM and check your phone model to see if it’s compatible with an eSIM.

A mobile virtual network operator (MVNO) is a telco that does not own the network which it uses to provide mobile services to its customers. Many SIM-only providers are MVNOs, meaning they resell access to the Telstra, Optus or Vodafone networks – usually at much lower prices than the big three will offer themselves.

For this reason, you’ll find that we frequently recommend MVNOs for some of the best SIM-only plans in Australia. Some of the major MVNO brands are Amaysim (Optus), Belong (Telstra), Circles.Life (Optus) and Everyday Mobile (Telstra).

There are three sizes of SIM card that you can get for your phone, and the one you need will depend on your handset. It’s been a while since the traditional, so-called standard SIM (15 x 25mm) has genuinely been the staple in new phones.

Instead, any phone you’ve bought within the last five or so years is much more likely to require a micro (12 x 15mm) or nano (8.8 x 12.3mm) SIM – the iPhone 5 was Apple’s first mobile with a nano SIM, while Samsung began using the smallest size in its Galaxy S6.

Before you purchase your new SIM, double-check the manufacturer’s website to see what size you require. And if you’re simply not sure, most networks now send out a triple SIM, so you'll get one of each size.

Because most SIM-only plans come on a lock-in contract, and you can change your plan up more easily than you could on a lengthier 24- or 36-month contract, it’s less crucial to get your data requirements perfect from the start. But if you’re considering a contract of any kind, or just put a personal pride on getting things right the first time, we’ll help you find the data sweet spot.

Firstly, check your phone to see how much data you’ve been using to date, and whether you have the tendency to use more than your current allowance every month, or less. This should provide a good estimate of how much a new plan needs, but if you’re still unsure, here's some general data-use guidance:

0-5GB: Tiny amounts of data on SIM-only plans could be a blessing or a curse. If you’re aiming for a SIM to put in a rarely used phone that will scarcely be away from Wi-Fi then this amount makes some sense. But if you end up with a plan that only has 5GB or less because your head’s turned by the incredible price, you could ultimately end up paying more if you continually go over your allowance.

5-15GB: If your phone is almost always connected to a Wi-Fi network at home, and you’re a fairly light data user during the times you’re out and about, then a data plan between 5-15GB could work for you. If you just use Google Maps, occasionally stream music and check social media, plans in this bracket will give you enough freedom to safely scroll while you’re away from Wi-Fi.

15-50GB: A report published in December 2023 by the Australian Competition and Consumer Commission (ACCC) found that the average mobile user in Australia uses 15.9GB of data a month, so phone plans in this bracket will be best for most people. If you like to stream music or videos and download podcasts when you’re on 4G or 5G, or you use map apps on a daily basis and generally have a data-intensive lifestyle, this is likely to be the cap you should be looking at. Keeping under 50GB can keep your costs affordable too.

50-100GB: You’re going to have to be a real data-drainer for more than 50GB a month to be necessary. This amount will be helpful if you download apps or other large files on the go, stream in HD, frequently use your phone as a hotspot or work from somewhere that doesn’t have Wi-Fi.

100GB-unlimited: 100GB+ plans are for the truly heavy users; let’s be frank – if you’re using this much per month, you’ve either got a serious YouTube/TikTok addiction, or you’re tethering to your phone as your only internet connection. Unlimited data plans aren’t particularly common, with the small MVNO Felix being the only telco to offer a truly unlimited mobile data plan. Felix caps its speeds at 20Mbps, which is still good for streaming video and music. But for most people, unlimited data simply isn’t necessary.