You don't have to choose between your home number and affordable data abroad.
This is the question we hear most often from first-time eSIM users: "If I switch to a travel eSIM, will I miss calls to my regular number? What about the verification texts from my bank?"
The short answer: you don't have to switch at all. Most modern phones can run two lines at once. Your physical home SIM stays in the phone, active for calls and texts. The travel eSIM sits next to it, handling all your data. Both work at the same time.
Here's how to set that up properly, and the one setting that makes or breaks it.
Dual SIM is the whole trick
Most phones released in the last several years support dual SIM: one physical SIM slot plus at least one eSIM. When both are active, your phone is registered on two networks simultaneously.
That means you can assign each line a job:
- Home SIM: calls and SMS. Your number stays reachable. Banking codes, delivery notifications, calls from family — all of it still arrives.
- Travel eSIM: data. Browsing, maps, messaging apps, everything that uses the internet runs through the local-rate eSIM instead of your home carrier's roaming rates.
Your phone handles the split automatically once you tell it which line does what. You'll find this in your SIM settings, usually under something like "Cellular" or "Network & internet," where you can choose a default line for data and a default for calls.
The setting that actually saves you money
Setting the eSIM as your data line is step one. Step two is just as important: turn off data roaming on your home SIM.
Why? Because even when the eSIM is your default data line, a home SIM with roaming enabled can still pass data in certain situations — and that data gets billed at your home carrier's roaming rates. Switching roaming off on the home line closes that door completely.
With roaming off on the home SIM:
- Calls to your number still ring through.
- SMS still arrives, including those six-digit verification codes.
- No data ever touches your home carrier's rates.
That's the whole arrangement. Voice and SMS on one line, data on the other, and a hard stop on accidental roaming charges.
Label your lines before you fly
A small thing that saves real confusion: give each line a clear name.
Phones let you rename SIM lines — instead of "Primary" and "Secondary," call them something like "Home" and "Travel Data." When you're standing in an arrivals hall checking why something isn't connecting, you want to know at a glance which line is which.
While you're in those settings, do a quick dry run at home:
- Confirm the eSIM is installed and shows up as a line. If you haven't installed one before, our installation guide walks through it step by step.
- Set it as the default for data.
- Set your home SIM as the default for calls.
- Turn data roaming off on the home SIM (and on, if required, for the eSIM — travel eSIMs often need roaming enabled to work, which is normal and doesn't cost extra on a prepaid plan).
Five minutes at home beats troubleshooting on airport Wi-Fi.
One thing to check with your carrier
Receiving texts abroad is usually free or cheap on most carriers. Usually — but not universally. Policies vary, and some carriers charge for received calls while roaming, or have unusual rules for SMS.
So before you fly, check two things with your home carrier:
- What does it cost to receive an SMS abroad?
- What does it cost to receive a call abroad?
If receiving texts is free, you're set: verification codes will keep arriving at no cost. If your carrier charges for incoming calls, you can simply let unknown numbers go to voicemail and return calls over a messaging app on your eSIM data.
The takeaway
Your home number and a travel eSIM aren't competing for the same slot. They're two lines doing two jobs: the home SIM keeps you reachable, the eSIM keeps you online at local rates.
Set the eSIM as your data line. Turn off data roaming on your home SIM. Label both lines so you can tell them apart. Confirm your carrier's incoming SMS policy before departure.
Do that once, and the question of "will I get my bank's code abroad?" stops being a question at all. Whether your next trip is a single country or several, you can browse where Openline works — or pick up a global eSIM and set it up before you pack.
