The short answer: data is usually enough
If your trip is a holiday or a short working visit, the practical question is not "how do I get an Australian number" but "what still needs one". For most travellers, the answer is: very little. Everything that matters day to day — maps, ride-hailing, restaurant bookings, messaging, banking apps you already have — works over a data connection.
A prepaid travel eSIM such as the Australia eSIM plans on the store page gives you mobile data on the Optus network. It does not add a local number or ordinary voice minutes, and that is by design: it is a data product, and it is priced for a trip rather than a contract.
When an Australian number is genuinely required
There are a handful of situations where a local mobile number is not optional:
- Australian bank account opening. Banks commonly send a one-time code by SMS to an Australian mobile number. A VoIP number is often rejected for this.
- Government or tax registrations. Anything that ties a record to an Australian mobile number, including some working-holiday and tax steps, expects a number you can receive SMS on.
- Local voice calls to businesses. Some small operators, trades and clinics still only publish a landline or mobile, not an app or web form.
- Long stays and rentals. Landlords, share-house platforms and employers may want a number you can be reached on.
- A number you keep for months. If you are staying long enough to need continuity, a local prepaid SIM is the more natural fit.
If none of those apply to you, the rest of this article is about making a data-only plan work well.
When it is not: apps that work over data
Almost every travel task people worry about runs over data alone:
| Task | Needs an AU mobile number? | Notes |
|---|---|---|
| Ride-hailing (Uber, DiDi, 13cabs app) | No | In-app messaging and calls run over data |
| Maps and public transport | No | Offline maps work without any connection |
| Hotel, tour and restaurant bookings | No | Email, web forms and app chat |
| Messaging home | No | WhatsApp, Messenger, iMessage over data |
| Banking apps you already hold | Usually no | Your home bank's app works over data; SMS codes go to your home number |
| Opening an Australian bank account | Yes | Usually requires an AU mobile for SMS |
| Calling an Australian landline | Sometimes | VoIP can do it, but the number is not a mobile number |
| Work calls on a local number | Yes | Employers usually want a reachable AU number |
If you are heading to a specific city or region and want to check your plan against the route, the destination guides are the place to start — for example eSIM for a Sydney trip or eSIM for Melbourne.
VoIP numbers vs mobile numbers, plainly
A VoIP (voice-over-IP) number is a number that lives on the internet. You can call and sometimes text from it, usually through an app. It looks like a phone number, and it can be useful for calling a restaurant or a tour operator.
It is not the same thing as a mobile number issued by an Australian carrier. Two differences matter for travellers:
- Verification. Many banks, government services and some apps check whether a number is a real mobile number before sending an SMS code. VoIP numbers are frequently rejected. Do not assume a VoIP number will get you through identity verification.
- Receiving SMS. VoIP services vary in whether they can receive SMS at all, and whether Australian senders will deliver to them. A number that can make calls may still not receive a bank code.
So: VoIP is fine for talking. It is not a substitute for a mobile number when a business or agency needs to text you.
What receiving SMS means for bank verification
If your trip involves opening an Australian bank account, applying for a tax file number, or any step where a code is texted to you, plan on having a real Australian mobile number for that step. That usually means a local prepaid SIM from an Australian carrier, bought after you arrive, with the ID the carrier requires.
A travel eSIM is not the tool for that job. It is the tool for everything else: the data that keeps your maps, bookings and messages running from the moment you land. The store's own copy is explicit that these are prepaid mobile-data products and that they do not add a local number or ordinary voice minutes — so if you need SMS verification, keep that separate from your data plan.
One practical middle path: keep your home SIM active for the verification messages your home bank sends, and use the travel eSIM for data. Check your home carrier's roaming terms before you fly, because keeping a line active for incoming SMS can involve separate charges from that carrier.
Tourist SIM options that include a number
If a number is genuinely required, your options are:
- A prepaid SIM from an Australian carrier, bought in a shop or at the airport after arrival. This is the standard route for a real Australian mobile number, and it typically requires ID.
- A prepaid eSIM from an Australian carrier, where the product record says it includes a number and voice or SMS. Not every carrier eSIM is data-only, and not every one includes a number — check the product's own terms. Telstra eSIM Prepaid walks through how that route works.
- A data-only travel eSIM for everything that runs over the internet, with a separate solution for the rare SMS you need.
For most readers, the third option covers the trip and the first two are only worth the extra step if you have a specific verification or voice requirement.
A decision checklist by trip type
| Trip type | Do you need an AU number? | What to buy |
|---|---|---|
| Short holiday, 1–2 weeks | No | A data-only Australia eSIM for the length of the trip |
| Multi-city holiday | No | One eSIM with enough data for maps, uploads and video |
| Working holiday | Often yes | Data eSIM for daily use, plus a local prepaid SIM for the number |
| Long stay, 1 month+ | Usually yes | Local prepaid plan for the number; eSIM for extra data |
| Business trip with local calls | Yes | Local number, or a VoIP service if calls only |
| Road trip or campervan | No | Data eSIM, plus offline maps downloaded before you leave |
Before you buy, check two things on the store page: that your exact phone supports eSIM and is carrier-unlocked, and that the plan's validity matches your trip. Validity and data are chosen separately — a longer validity period does not create more data. If you are staying a while, eSIM for a month in Australia covers the longer-trip maths.
How the plan actually starts
One detail that catches people out: a travel eSIM plan starts when it first connects in the country, not when you buy it or install it. That means you can install it at home over Wi-Fi, land, and switch the data line on when you arrive — no wasted days. Select the travel line for mobile data and follow the roaming setting in your order instructions, and check any home-line charges separately with your own carrier. If you want the step-by-step version, see how to install an eSIM for Australia.
What to buy
If your trip does not involve opening an Australian bank account, applying for a tax file number, or taking local voice calls on a number you hand out, buy data and skip the number. The Australia eSIM store page lists the live allowances and validity on the Optus network — pick the data and duration that match your itinerary, check your phone's compatibility, and install before you fly.