T-mobile users, I have a question

It depends on your plan. My plan, for example, includes iree calling and data while traveling in a list of countries but a small charge to call the US from abroad and variable charges per minute to call most countries other than Canada and Mexico from the US. There is an available add on monthly charge for what they call "stateside calling" from US to a list of places, but I do not have that. I rarely makke international calls from home but if I do I use Whatsapp wifi calling (free) or a very old skype account that still has some ctredit on it.

I don't know if it is relevant, but T Mobile no longer exists in the UK, customers were moved to EE.

It sounds like you are calling from the U.S. to the U.K.
The international roaming with free data and 25 cent a minute phone calls applies when you are traveling outside of the U.S., not when you are calling from within the U.S. to another country.
https://www.t-mobile.com/support/coverage/international-roaming-services

There is a different add-on plan for calls from the U.S.
https://www.t-mobile.com/coverage/international-calling

I made the same mistake a few years back.

We have T-Mobile and added "Family Stateside International Talk" for unlimited calls/texts from the US for $20 for both of our lines. Otherwise we would be charged the per minute rates.

My T-mobile plan (that I’ve had for many, many years) includes free data and texting when traveling out of the US and charges 25 cents per minute for actual phone calls. Since I almost never make a phone call, but use plenty of data and texts, this plan works great for me. I have used it with no problems all over the world.

I have a Tmobile Magenta 55+ plan, and am very happy with using it internationally. However, I just had a bad experience making two calls from Michigan to Ireland. The calls totaled 27 minutes, and I was charged $91.57 for those calls. I was dumbfounded.

Then I re-read all the fine print and realized that I had "wifi calling" activated on my phone. Seems that all wifi calling calls are considered international. And calling Ireland from the US cost $3.00 per minute. Sheesh.

You might check to see if you have wifi calling activated.

I have T-Mobile Magenta and have no complaints with the service in the UK. However, if you make an international call from the US it will be pricey. My flight to London was cancelled over Christmas, and I was going to be a day late arriving at my hotel. I called the hotel in London to make sure that I wasn't marked as a "no show." The bill for the call from the US was $77. I'm sure I could've handled the problem with an email, but thought i'd call instead. I will definitely only make an international call in the future if it is absolutely necessary.

Thanks for all the input. All very useful! Travelguy nailed it. We had the wifi calling on. Fortunately, they were able to reverse the charges for us!

Thanks again.

The OP is talking about calls originating in the US to Europe.

That is completely different than calls made while you are traveling in Europe.

You can add the T-Mobile Family Stateside International Talk for $20 a month. However, it will not start until the next billing cycle.

An alternative for calls from the US is using Whatsapp for calling over WiFi.

We also have Magenta+55 and always use wifi calling at home as we get 0-1 bars in our building. Never been charged for calls made inside the US, so it's incorrect that all wifi calls are considered international. For calling from the US to other countries we use Whatsapp which is also wifi but free of charge.

I just checked, and found that I had WiFi calling enabled on my phone. I used WhatsApp when I made the call from the US to UK, and T-Mobil still charged me. I received a message that said I may be billed by my carrier, and they sure did.

Plans change all the time. The OP is going to have to read their plan (its on line) and see what they get and what they do not get.

I have TMobile and I am on an extended vacation in Europe. I keep the phone on airplane mode + wifi on and I use WiFi calling several times a week. Either calls coming in or me calling out. Works perfectly and costs nothing. When I need a US IP address I turn the network connection, just long enought to take care of the business, then back to WiFi. I generally dont exceed my data allowance so that costs nothing too.

To Stacie, I'm no expert on this but my understanding is that you cannot use Whatsapp to call a landline and that the party you are calling has to have Whatsapp.. Perhaps the London hotel number you called was a landline? Skype, now largely obsolete, does let you call a landline number from a cellphone for a few cents.

CD in DC you are correct about WhatsApp. But TMobile wifi calling functions just like a network call. With wifi calling i can call from anywhere in the world, any number in the US for the cost of the data. The only strange thing is that it isn't always my number that shows up on their phone. With wifi calling, almost every day I get US phone marketing calls in Europe. I have no idea how or why it works, but it does.

Those considering a change in their cellular-service providers and looking at T-Mobile might want to look at Google Fi as well. As someone who spends a lot of time in Europe (using quite a lot of data) but is a light user of data when home in the US, I saved a lot of money by switching from T-Mobile to Google Fi. My basic monthly charge (with no data included) is about $20; I don't pay much more than that for the seven months per year when I'm at home. I'm saving even more now that I've switched to using eSIMs in Europe to avoid Fi's high per-GB charge for data on my plan. (Other plans are different.) So much depends on the customer's usage pattern.

Google Fi has a reasonable charge for making calls from the US to many countries. A quick check showed 20 cents per minute to France, for example. I think I pay about 25 cents per minute on the rare occasions I need to call from most countries in Europe back to the US. I get free texting in both directions, which is very helpful when traveling.

CD in DC- thanks for the info. I didn’t even think about the receiver of the call being a landline. I was calling Premier Inn, so definitely a landline.

Im glad that I don’t need to often make international calls. It was certainly a case of first time sticker shock.

Stacie you are talking about three different things. It’s okay, it blew my mind when I tried to figure it out.

1. WhatsApp: only calls other WhatsApp enabled phones. The calls will cost you whatever your phone plan data costs you. Most of us have some data that comes with the phone plan so if we stay under that number it’s free. If you are on Wi-Fi, it should always be free.
   
2. T Mobile Wi-Fi Calling: This I don’t know much beyond knowing it works, and it works well. First I enabled the Wi-Fi calling (not really, it came to me working), but then since this stuff makes me nervous whenever I am on Wi-Fi like my home in Budapest or just about any bar or restaurant in the world these days (just ask for the password) I put my phone on Airplane Mode which turns off the Network connection and I turn on my Wi-Fi. Now phone calls are guaranteed free, and I can call any phone number in the free world.
   
3. T Mobile Network: If you got charged for an international call, then you were using the network not Wi-Fi Calling and not WhatsApp unless you were getting charged for Data on a network WhatsApp connection.
   

Having said all of that, T Mobile and all the companies change their plans almost daily. Quite often people remain on the original plan they signed up for even if that plan has changed 6 times …. They still get the original deal. So what you have and what I have even with the same carrier like T Mobile and even with the same plan name could be different.

If it works for your lifestyle the sim cards can maybe save you money. Acraven is known for smart moves so I would trust what she says. They don’t work for me because I am old fashion and still need to answer my home phone number and still need to do a lot of third-party identifications ... you know where they text you a code to put into the bank web page. I had to deal with that 3 times today from two different financial institutions. I also like being able to pretend to be in the US, which i can do with a US phone number and a US IP address. That means with my US phone my google searches think I am in Texas, I can renew my drivers license, I can log into the Orvis website.