Can an iphone 3 sim card work in iphone 4s phone?

Can an iphone 3 sim card work in iphone 4s phone?

The iPhone 3G/3GS use regular SIM cards and the iPhone 4S uses a micro SIM which is smaller. You may be able to cut your SIM to work in the 4S but it's not a 100% guarantee it'll work.

NO, the iphone3g has a regular sized sim whereas the 4s uses micro-sim. However you can cut the bigger regular sim to the size of a micro sim carefully.

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