Tech Talk

If you a) want to save some money; b) don’t want to be tied into a lengthy contract; c) already own a perfectly fine phone; or d) all of the above, then going SIM-only is a logical choice. In fact, you’re probably in one of two situations if your thoughts are turning to a SIM-only mobile plan:

1. You’re coming to the end of your contract and your phone is still fighting fit (if not, then head to our best mobile phones deals page to see what plan you can grab alongside a phone). On a good SIM-only plan, you’ll wind up paying much less than you are under contract, and you can often stick to a rolling month-to-month arrangement so that if your circumstances change, you can change with them.

2. It’s time for a shiny new smartphone and you want to get the best value humanly possible. You’ll have to find a few hundred bucks (or thousand at this stage) upfront for the handset, but if you choose a sensible SIM-only plan you’ll end up better off at the end of it all. Plus, if you’re a commitment-phobe, most SIM-only plans don’t require you to sign up for two years of handset repayments, like you would with a normal contract.

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 Woolworths Mobile (Optus).

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.

Unlike with a standard post-paid mobile plan, there’s a lot more flexibility available when it comes to how long your SIM-only plan will last. Because there are no handset repayments to factor in, 2-year commitments are virtually unheard of here, with the norm now being rolling one-month contracts for ultimate flexibility.

You can occasionally get better prices if you tie yourself in for 12 months. But sticking to one month at a time means that you could effectively hand-pick a new plan to suit you every 30 days or so.

Because you can change your plan up more regularly than on a normal, lengthier contract, it’s less crucial to get this nailed from the start. But if you’re considering a contract of any kind, or just put a personal pride on getting things right first time, then 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. Then, if you’re still unsure, check out our guidance:

0-5GB. Tiny amounts of data on SIM-only plans could be a blessing or a curse. If you’re putting it in a rarely used phone that will scarcely be away from Wi-Fi then it makes total sense. But if you end up with one because your head’s turned by the incredible price, then you could end up paying more if you continually go over your allowance.

5-10GB. For anybody who needs data for little more than the occasional Google Maps route planning, 10GB plans come cheap and give you much more freedom to scroll away online away from the Wi-Fi.

10-50GB. If you like to stream music and download podcasts when you’re out and about, or you use maps 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 at an affordable point.

50-100GB. In this bracket, you’re going to have to be a real data-drainer for this to be necessary. This amount will be helpful if you download apps or other large files on the go, stream in HD, or work from somewhere that doesn’t have Wi-Fi.

100GB-unlimited. Unlimited data plans aren’t particularly common, with only Vodafone and Felix offering a truly unlimited data plan. Vodafone says its plan gives you the fastest speed the network can deliver at the time, while Felix caps speeds at 20Mbps, which is still good for streaming video and music. But for most people, unlimited data simply isn’t necessary.