iPhone 17 Pro: AT&T international data charges with roaming off

on iPhone 17 pro, I spend a lot of time in France and have a 2nd SIM for France. AT&T keeps charging for IDP (International Day plan) based on a tiny amount of data usage 10-15 days per month (0.01 mb). My data is set as roaming off, and all data is set to use the international SIM.

AT&T can't tell me what app is using the data, but they insist that it's being used and therefore I have to pay $12 per day (up to 10 days per month).

AT&T and Apple both tell me to put my phone in airplane mode, which is ridiculous because then I can't make/receive calls when I'm international. They also tell me to turn my US number off when not in the US, which is also ridiculous, because I need to be able to be contacted. That's why there are 2 SIMs.

The dates/times that AT&T says I've used data do not align with any days or times I've made calls or received texts or anything else.

I have also gone through any app that could be sending tiny amounts of data (even when set to 2nd SIM) and turned data off for them.

I have found another link that exactly describes the same problem, but with no clear answer: https://www.reddit.com/r/ATT/comments/1vs911y/001_mb_data_with_roaming_off_triggering_idp/

Any suggestions on how to fix this are greatly appreciated, as AT&T is charging me an extra $120 per month because of this.

Posted on Nov 9, 2026 9:19 AM

1 reply

Mac Jim ID

Level 10 (105,996 points)

Nov 9, 2026 9:56 AM in response to Rick-in-Nash

The solution is to choose a cellular provider that will not be charging you. Notice the other example you provided is also AT&T. If they are not going to tell you exactly why you are being charged or how to prevent it on a device that was provisioned through their SIM card, then you would be better off with another service.

Same thing happens on Android too using AT&T as you can see in this other Reddit post.

This is extremely helpful, thank you. You’re on Android too, so there goes my simple “maybe it’s just an iOS bug” theory 😂. I just disabled data at the AT&T account level as well. I guess if that fixes it, the remaining mystery is why we have to go as far as BBB to get AT&T to actually investigate it.
Same issue here, on Android (Samsung S23+), so it's not an iPhone thing.

https://www.reddit.com/r/ATT/comments/1vs911y/001_mb_data_with_roaming_off_triggering_idp/