using Airalo in Italy

1. Yes, your phone must be unlocked in order to add an eSIM.
2. Airalo has Local eSIMs (for a single country), Regional eSIMs (for a region, like all of Europe), and Global eSIMs (for 137 countries). Only the Global eSIMs include telephone. You can set your phone to use either SIM for calls, texts, and data. You are right that the S25 supports two eSIMs, so you don't have to switch between them when receiving calls. They'll both be active simultaneously. It's when you make a call or send a text that you'll have to determine which SIM to use. On the Galaxy, you can set it to ask every time you make a call if you want, or you can set it to use one or the other. And you can change the setting at any time. WhatsApp will work just fine. No one will know what SIM you're using.
3. When you are on WiFi, you won't be using the SIM, you'll be connected directly to the internet via the WiFi. So yes, there will be no charges. You don't have to turn off the eSIM to do that. If you don't want to be charged by AT&T, you can completely disable that SIM and use only Airalo.

I would strongly recommend you get your elderly parents set up with WhatsApp so they can always reach you and you an always reach them. If you do that, you won't have any need to toggle back and forth.

On your last question, correct. When you are connected to WiFi, you are not going to be using the Airalo data plan.

Thank you, Lane, this is very helpful.

Ah. I didn't realize there were local/regional/global eSIMs. Am I understanding correctly then that a local eSIM for Italy will only work within Italy, and is data only, no texts or calls? If I want texts and calls I'd need a global eSIM with data, voice, and text?

So, if I have a local Italy data only eSIM installed, and an incoming call from the US comes to my US number, will my phone ring, if my AT&T eSIM is disabled? What if I put my phone on Wifi Calling and I happen to be on wifi when a call comes in, will it ring then?

And am I correct in that SMS text messages will not come in at all, even on wifi, unless I enable my AT&T eSIM and pay the international daily fee?

My parents do indeed have WhatsApp and currently use it. No issues there, thankfully.

So basically, I should let everyone know to use WhatsApp to reach us, either texting within Whatsapp or voice calls within whatsapp. We will be able to text or voice call each other using Whats app while in Italy, if we all have data only eSIMs, right?

Wait, another dumb question, but Facetime would work, too, right?

My mother has whatsapp and is well versed in using it but my father in law doesn't. I was thinking we'd get him set up, but, he has an iphone and so does my husband... if he can use Facetime, which he already knows, then we're set.....

FaceTime can be used over Wi-Fi or Cellular data between two iPhones. If you have access to stable and fast Wi-Fi; you should be able to use FaceTime over it between two iPhones without consuming cellular data.

Phones will need to be unlocked to use an Airalo eSim. If you purchased your phones through AT&T they are likely locked, but call and ask them. AT&T will unlock phones if they are paid off in full and have been active on the network for at least 60 days, but I don’t believe they do this automatically, you have to ask for it.

On phones that allow dual SIMs, you can set them up so that both SIMs are active at the same time. No need to toggle between them. I’m not sure how Samsung phones work, but on the iPhones, you would be able to set up the AT&T SIM to send/receive Phone Calls and Texts and the Airalo SIM to send/receive Data.

Airalo Local SIMs are Data only (no phone calls or text) and only work in the specific country. Both WhatsApp and Facetime use Data or WiFi, so if you just rely on those apps, you wouldn’t need to use AT&T’s international plan.

Just a note, you may want access to your USA phone number if you use it for any two-factor authentications (like for your credit card or bank account).

Yes, for Airalo (or most eSIM providers), your phones do need to be unlocked. You might want to double-check with your carrier to confirm.

When you’re using an eSIM like Airalo, you’ll get a local data-only connection, so you can’t receive regular calls or texts to your US number unless you switch back to your AT&T eSIM

Just make sure data roaming is fully disabled to be safe from additional roaming bill. You can still receive iMessages and WhatsApp messages over WiFi or eSIM, but regular SMS might not come through unless you reactivate your AT&T data.

I used Airalo before, it’s pretty good and switching between eSIMs is not too complicated. But recently I’ve been using Jetpac eSIM because they let you hotspot to other phones (great when traveling as a family!) and they also offer free access to WhatsApp which can be super handy