TMobile in Europe

Explore here: https://www.t-mobile.com/travel-abroad-with-simple-global

I haven't yet used my new T-Mobile plan in Europe, but as I understand it, I will pay for phone calls on a per-minute basis. It's not terribly expensive, but it is not free. Your travelers will probably want to communicate primarily by texting. They may want to plan on using a Wi-Fi-based calling app when it's convenient and they need to make a call. Others here can provide more information about things like Skype.

Check online for T Mobile's international plans. The company is owned by the German telecom company, and they are the cell company for a number of countries within Europe. Their service should be good.

T-Mobile offers unlimited 2G (slow) data when traveling internationally. The data allocation of your US plan will be irrelevant when traveling. If you want data faster than 2G, you'll need to buy "data passes" from T-Mobile while you travel. The data speed may be fast enough or it may be frustratingly slow. (While on WiFI, this is not a factor - your phones will be as fast on WiFi as they are at home, assuming the WiFi you use is fast.)

Make sure you don't have an old T-Mobile plan that doesn't allow international roaming. If it's "Simple Choice" or newer, should be fine; call T-Mobile to confirm.

Calls are 25 cents/minute while in Europe with T-Mobile. If your phones support the "WiFi Calling" feature, you can make free calls home to the US while your phone is connected to WiFi. If not, you can install Google Hangouts on your phones. This will let you make free calls home to the US, even to landlines (say to call your bank or airline or whatever - handy when you might be on hold for a while and not paying 25 cents/minute for that).

They give you free unlimited texting as well.

You won't need to buy a new SIM if you stick with T-Mobile. You CAN buy a SIM in Europe for the faster data, if your phone is unlocked. A European SIM bought in one country may work in the others (depends on the mobile company and country you buy the SIM in - many allow free EU roaming, some don't allow it at all). If you have a European SIM in your phone, you won't have access to your US phone number until you put your T-Mobile SIM back in.

T-Mobile offers unlimited 2G (slow) data when traveling
internationally.

In practice the speeds are often faster. Be sure to go into the "cellular" setting of your Iphones and turn on the "roaming" switch and your phones will automatically work when you land in Europe. Nothing more you need to do, no need to contact T mobile about your travel plans.

I'm a happy T-Mobile customer and travel to the EU 1-2 time a year. Have used my IPhone from Turkey to Portugual and even on the Camino in Spain last year and had super coverage. You don't need to do anything when you enter the EU except take it off Airplane mode when you land. It worked in Morocco with no hiccups except that calls other than using Wifi were over $2.50 a minute as they have no partner there.

Just make sure "data roaming" is turned on in the phones.

It worked in Morocco with no hiccups except that calls other than
using Wifi were over $2.50 a minute as they have no partner there.

According the the Tmobile site, the current rate for calls in Morocco is .25 a minute.

We were in Greece earlier this year with t-mobile and it worked very well. We had to call back to US a couple times and calls were clear. It was not that expensive. Texting was free which is what we mostly relied on.

OP may find this recent thread of interest:

https://community.ricksteves.com/travel-forum/tech-tips/t-mobile-overseas-options

T-Mobile offers unlimited 2G (slow) data when traveling internationally.

T-mobile's international unlimited data roaming speed is based on the local network, and can vary drastically from location to location. This spring I was pleasantly surprised by the LTE speed all over Sicily. But no such luck in Spain this fall, 2G/3G only. But still good enough for web browsing, e-mail, and Google Maps.

For those needing high speed, I found the SIM prices in Europe to be very reasonable. A tiny fraction of a trip's cost, and good value for the peace of mind.

Just to add a data point about T-Mobile. My 2018 experience in France and the UK was that, while my phone often connected on the 4G LTE network, my data speeds were still throttled down to 2G speeds.

Since text is free on the T-Mobile international plan, that's a great way for your wife and daughter to communicate with each other while abroad.

When you are on T-Mobile, your phone will always connect to the fastest network available. If that's LTE, then you'll connect to an LTE network. That doesn't mean you'll get LTE speeds. T-Mobile throttles your data to 2G speeds - though it seems even that may vary. When I last used T-Mobile in 2016 in the Baltics and St. Petersburg, I got LTE almost everywhere. My speeds were usually OK - but slowed to a crawl when I'd try to stream video (usually accidentally) or upload something.

Beyond that: sure, if you can connect only to slower data local networks - whether you have T-Mobile or some local SIM - things are going to be slower. Some older US phones may only support connection to 2G "Edge" data networks, so that's going to be slow no matter what T-Mobile does or doesn't do.

I'm currently in Greece and have been using both a phone and tablet with T-Mobile. When I'm on a WiFi network outside of USA, my international calls are free. The connection from my Athens hotel WiFi was incredibly clear.

Downloading books on to my tablet has been a little slow but now that I know, I can plan around it.

I've been texting lots of photos back home without any problem.

I'm currently in a smaller town and the wifi speed seems to vary.

I didn't need to purchase a SIM card and international calls are $0.25 a minute if I'm not on Wi-Fi.