The big problem with your Telstra or Optus phone plan

If you're after a mobile phone plan, there are plenty of choices, whether you fancy postpaid or prepaid, heavy or light data usage, from more than 30 providers.

Competition breeds lower prices, which saves us all money. There's just one problem here.

Most of us haven't switched, and in many cases won't switch, away from the big three brands, Telstra, Optus and Vodafone.

Our research suggests 75% of Australians have a mobile plan with one of the big three. What's more, 57% of those consumers wouldn't shift to another plan even if it saved them money.

In these belt-tightening times, it's worth diving into why consumers stick with the big brands: 32% of the ones we surveyed figured they were already on a great deal, so there was no need to switch; 15% were worried about reliability issues; and 10% simply didn't want to spend the time involved in switching to a new provider.

If you've been sitting on your mobile plan for more than a year or so, then the odds are extremely high your "great" deal has been surpassed by the market, where larger data allocations and falling prices have long been the norm.

Your telco won't always tell you about a new deal - it's in its interests to make as much money out of you as possible - but researching new deals takes 60 seconds or less.

Then there's the argument about the time it takes.

By law, you're entitled to shift your mobile number to any provider you like and it is obliged to handle the trickiest parts of that process for you.

Most providers offer a simple online sign-up process and many will mail you a SIM card for free if you sign up. So all you need is your driver's licence or passport details, as you would for any new mobile plan.

But, I hear you cry, a small provider doesn't have the resources of its big competitors. Surely their networks aren't as reliable?

Here's the trick with mobile networks in Australia. While there are more than 30 mobile brands, there are only the three networks belonging to Telstra, Optus and Vodafone.

They all sell access to other brands. Optus and Vodafone don't make any distinction in the access that their "virtual" partners get to their networks, so if you're already on Optus or Vodafone there's no difference at all, except to your hip pocket.

Telstra does make a distinction with access for partner telcos such as Woolworths Mobile or AldiMobile, offering up "parts" of its network.

Again, though, that's really only a concern if you travel to some of the most remote parts of Australia regularly or if you're obsessed with network speeds.

For most of us, the speeds and coverage will be just fine for everyday use, especially in metropolitan or larger regional centres.

So how should you shop for your next mobile plan? Everyone's needs vary, but as a starting point you can take unlimited standard calls and texts as a given.

Even the cheapest plans will include that, so what you should do instead is consider your data needs and, to a lesser extent, your need for features such as international calls or data roaming.

The practical reality here is that data inclusions are increasing all the time and that's a feature that won't head backwards with the introduction of super-fast 5G networks later this year.

If your current plan has enough data for your needs, check you can't get the same inclusions on a cheaper plan on the same network.

If you constantly get stung with excess data charges, look to higher-tier plans. It's nearly always cheaper to jump up a tier than pay for extra data.

Telco brand loyalty doesn't have to be a bad thing if there's value for you in the extras you get, whether that's Optus Sport, Vodafone's "contract free" mobile handset deals or Telstra's new Telstra Plus customer loyalty scheme.

However, thinking that you're on the best deal just because you're ensconced in a plan from one of the major carriers is a potentially expensive assumption.

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