Where can I find my SIM card numbers. I have two phones and now got them mixed up.

Of course you can find them on the SIM card itself which are printed on the opposite side of the gold colored contacts.

You can also find this information in your iPhone. Open Settings ➔ General ➔ About ➔ ICCID : Here you will find the SIM number that you are looking for.

Axel F.