The dimensions of a standard SIM card, micro SIM card and nano SIM card. For more information, see our comparison of the different SIM card types. Using Older Handsets. After changing to a smaller-size SIM card, it should normally still be possible to use

In simpler terms, it’s a small card that allows your phone to get service from a carrier. There are a few different sizes of SIM Cards available: Standard SIM, Micro SIM, and Nano SIM, each of those progressively smaller than the previous one. While all

Buy a new SIM card. You can usually find SIM cards for specific carriers (e.g., AT&T) in the carriers' respective stores, as well as online and in most tech shops. Your phone most likely takes a specific size of SIM card, so check the SIM card'