Calls routed to wrong SIM

I’m having an issue that may be similar to this: Dual SIM card selection software issue

I have a FP3 with two SIM cards. I had it set to “always ask” to determine which should be used for outgoing calls. But for incoming calls I would normally expect that when I receive a call that it would be taken on the SIM card corresponding to the number that was called. This does not appear to be the case though and it seems to randomly switch between the SIMs for incoming calls, resulting in expensive international calls. There also appears to be no option to choose the SIM when receiving calls (although I would expect for calls to be taken on the number they come in on).

Is there a way to ensure that the SIM card corresponding to the number called is used for incoming calls? Or is it normal behavior for it to randomly transfer calls to the other SIM for no apparent reason?

Thank you

You can’t switch SIMs for incoming calls. I think that you are seeing a cosmetic problem rather than a real issue that would affect calling rates.

In any case, if you have problems with SIM cards please tell us which operators you have and from which countries your SIM cards are.


I know it affected calling rates because I got the bill and calls to one number went to a different number. Operators are Google Fi (US) and 3 (UK).

Initially I had thought it was a cosmetic issue so I didn’t worry too much, but I just realized that was incorrect.

1 Like

Do you perhaps have forwarding set up at one of the operators so your calls get forwarded to the other number if one is not within reach?

Also, given you’re being billed for calls, this suggests that you are talking about outgoing calls? Or do you mean roaming costs?


No, I definitely do not have them forwarding to each other unless the phone somehow does that by default. The operators should also have no record of the other number - at least not from me.

It is only incoming calls. I am being charged for roaming because the calls are inexplicably going to a number other than the one called (as explained). For outgoing calls I am prompted for the SIM to call from and that works correctly.

Also note that it happens inconsistently. Most of the time it goes to the correct SIM but it goes to the wrong one often enough that it is clearly noticeable.

1 Like

Sorry to ask such a stupid question, but are you 100% sure that no one is calling you through the second sim number?


the Fairphone is not officially compatible with Fi, see >

Could you elaborate on your setup a bit? Where do you live, why the U.S./UK SIM split? What are you using the two different cards for, is it necessary to have both active all the time?

Best wishes,


That, and also I’d like to know to which number people are calling when the call appears on the ‘wrong’ SIM. Does this happen for one number or for both?


Well, I guess, it’s only the technical stuff, that is relevant.
Personal motives don’t have to be presented.

Could special circumstances be relevant, maybe, that the card, that is being called has no reception, or are you running a certain app, when this happens?
I guess, everything you can share could be important and helpful for the techies in this forum.

Just to reply- I’m absolutely sure no one is calling the second SIM number in these cases. People have one or the other number, not both.

Both SIMs seem to have reception when calls are redirected. I doubt a certain app is running when this happens because very few apps are on the phone.

I’m aware that Fairphone isn’t officially compatible with Fi, but it has never been an issue. I didn’t even have the Fi app on the phone in question or Google account logged in, so it likely isn’t an issue with something odd happening there. I have never seen calls redirect like this in the past and Google should have no record of the other number either (aside from any gained by both SIMs being used on same phone with no Google account logged in).

Hi, you’re still not quite clear about your situation. Are you in the US or in the UK at the moment?

And which number gets redirected, UK SIM to Fi SIM, or Fi SIM to UK SIM?

1 Like

I have a similar problem with FP2, have you received a solution?