Nokia manufactures a number of slide phones, from the bare bones 6500 slide model all the way up to the Nokia 5330 edition that allows you to watch TV on the go. One thing that all these phones have in common is the use of a SIM (Subscriber Identity Module) card inside the phone. These cards identify you to the phone network and also store contact information for your phone book. You can remove the SIM card from a Nokia slide phone when upgrading your service or changing providers fairly easily.
Place the Nokia slide phone face down on a flat surface.
Press the square button located at the top of the phone. Lift the back of the phone straight up and off.
Remove the battery by prying it out of the slide phone with your fingers.
Open the SIM card holder inside the phone battery compartment by lifting it up and swinging it back.
Slide the SIM card up towards the top of the phone to remove.
The above steps are just a guideline. Follow the specific instructions for your particular Nokia slide phone model.