When you change to a different iPhone, do you have to use your old sim card?

7kenpen7 wrote:

It's not a new phone, just a different phone, got from a friend, it has a sim card in it though.

After giving this info then yes, but assuming both phone are using the same phone carriers.

7kenpen7 wrote:

When you change to a different iPhone, do you also have to use your old sim card?

IF the new phone comes with sim card no.