can i put an old sim in a new phone
1 Use the SIM card from your old phone in your new phone so as to save your information. 2  This will is only an option if you have not changed carriers. 3  Switch carriers and keep your phone (or avoid having to buy a new one).. To make the switch, open your phone and either insert the new SIM card in place of the old one or remove your current SIM card and place it in your new device. There is a wikiHow article referenced below that speaks further to how this can be done. Ad.