Optus international roaming: how it works, what to check, and when a travel eSIM wins
Key facts
- Optus international roaming is generally billed per day of use or bundled into your plan, with a daily data allowance and reduced speeds after it.
- Rates and country zones change, so check your exact destination in the My Optus app before you fly and switch roaming on in advance.
- For trips of 1 to 2 days or plans that already include roaming, staying with Optus is the simplest option.
- VoaSim charges one price per duration for every destination: USD 23.90 for 7 days, USD 30.90 for 10 days, USD 42.90 for 15 days, with truly unlimited data.
- Install the eSIM before you fly but keep it off until you land — the validity clock starts at the first connection at the destination.
See the exact price for your dates
You are an Optus customer with a flight booked, and you want to know what happens to your phone when you land. Short answer: roaming works, but how much it costs and how much data you get depends on your plan and your destination.
This page explains the model in plain English, gives you a pre-flight checklist, and shows where a travel eSIM is cheaper. Both options are valid — it depends on the trip.
How Optus international roaming is billed
Australian carriers, Optus included, generally use one of two models for travel:
- Per day of use: you pay a fixed fee for each calendar day you actually use data, calls or texts abroad. No use, no charge that day.
- Bundled into the plan: some postpaid plans include a number of roaming days or an allowance in selected countries at no extra cost.
In both cases there is normally a daily data allowance. Once you pass it, speeds are usually reduced, or you buy another day/add-on. Country groups matter too: a destination in Zone 1 may be cheap while another sits in a higher tier or is not supported at all.
Rates and country lists change, so we will not quote amounts here. Open the My Optus app or the official Optus roaming page, type your exact destination and read the daily fee, the allowance and what happens after it. That takes two minutes and prevents the ugly surprise on the bill.
Pre-flight checklist if you stay with Optus roaming
Do this before you board, not at the arrivals hall:
- Check the destination in the My Optus app — daily fee, allowance, supported country list.
- Enable roaming on your account. Many plans need it switched on deliberately, and some require a travel pack purchase.
- Turn on data roaming in your phone settings once you land.
- Set a spend limit or alert if your account offers one.
- Check excluded services: cruise ships and in-flight networks are usually billed separately at satellite rates. Keep the phone in airplane mode at sea.
- Watch background apps: cloud backup, photo sync and updates can eat a daily allowance before breakfast.
If your plan already includes roaming days for where you are going and the trip is short, this is genuinely the easiest path. Keep your number, no setup, no QR code.
When Optus roaming is the better choice
We are not going to pretend the carrier is always wrong. Stay with Optus roaming if:
- The trip is 1 to 2 days — a stopover in Singapore or a quick Auckland run.
- Your plan already includes roaming for that country at no extra cost.
- You need to receive SMS codes and calls on your Australian number and cannot risk anything else.
- You are a light user: maps, messages, a few emails, and the daily allowance is plenty.
- Your phone is older than 2020 or carrier-locked, so eSIM is not an option.
Where the maths flips is on longer trips and heavy use: two or three weeks in Europe, streaming, tethering a laptop, video calls home. Daily fees add up, and the daily allowance is the part that usually breaks first.
VoaSim prices: one price per duration, every destination
VoaSim charges by how long you travel, not by where you go or how many gigabytes you burn. Data is truly unlimited: no cap, no throttling, no hidden fair-use clause. Prices below include today's 15% promo.
| Duration | Price (USD) | Per day |
|---|---|---|
| 5 days | 18.90 | 3.78 |
| 7 days | 23.90 | 3.41 |
| 10 days | 30.90 | 3.09 |
| 15 days | 42.90 | 2.86 |
| 30 days | 61.90 | 2.06 |
| 60 days | 106.90 | 1.78 |
Trips of 1 to 4 days pay the 5-day package. Maximum 90 days per eSIM. A second eSIM in the same order gets 10% extra off. Coverage reaches 170 destinations, and the Europe plan covers 50 countries with one eSIM, including the UK, Switzerland, Turkey, Norway and Iceland. Run your dates in the simulator to see the exact figure.
Side by side: carrier roaming vs travel eSIM
| Optus roaming | VoaSim eSIM | |
|---|---|---|
| Billing | Per day of use or bundled in plan | One upfront price per duration |
| Data | Daily allowance, reduced speed after | Unlimited, no throttling |
| Price by country | Varies by zone | Same for every destination |
| Your AU number | Stays active for calls and SMS | Stays active on your physical SIM (data only on the eSIM) |
| Setup | Enable roaming in the app | QR code by email, install before you fly |
| At sea | Satellite rates apply | Works on land at ports only |
Many travellers run both: Optus SIM on for calls and SMS with data roaming off, VoaSim eSIM handling all the data. See more comparisons in our compare section and roaming guides.
Installing a VoaSim eSIM without losing your Optus number
The QR code arrives by email within minutes of payment (card in USD via Stripe, invoice by email). Install it at home, before the flight, following the step-by-step iPhone or Android guide.
Key rule: your days start counting at the eSIM's first connection to a network at the destination. So install now, but keep the eSIM line switched off until you land. On Android, do not enable the eSIM's mobile data before the trip.
Your Optus SIM stays in the phone. WhatsApp keeps running on your Australian number. Just turn off Optus data roaming so nothing bills you in the background. Compatibility: iPhone XR or newer, Galaxy S20 or newer, Pixel 3 or newer, most phones from 2020 on. Dial *#06# — if an EID appears, your phone supports eSIM. Carrier-locked handsets must be unlocked first.
No signal on arrival? The free eSIM Rescue tool diagnoses any brand of eSIM. If ours will not connect and support cannot fix it, you get a 100% refund. More on how we operate in trust.
Why trust VoaSim?
Registered company with an invoice on every purchase, USD payment via Stripe with no hidden fees, human support and a guarantee: if the eSIM will not connect and support cannot fix it, you get 100% back.