Tracfone and Net10 sim card information

Tracfone and Net10 are both owned by the same company. Their support is provided by the same customer service people and comes from the same support centers. They both use the same sim cards. Their new sim cards can be used in any gsm phone for either Tracfone or Net10.

Tracfone's phones cannot be used for Net10 and Net10 phones cannot be used for Tracfone.
Once a sim card is placed in a phone and the phone is powered up, the sim card is locked to that phone and can never be used in another phone. If you place a new sim card in any phone, active or not and turn the phone on then the sim card is useless except for possible future use in that phone.

You cannot swap active sim cards in Tracfone and Net10 phones like you can with other gsm carrier's phones.
Tracfone and Net10 phones have proprietary firmware in the phones that will only recognize their sim cards. Also, their sim cards will not work in any phone that does not have their firmware in it.

You cannot unlock a Tracfone like you can with other gsm phones. In order to make one of Tracfone's phones usable with another carrier you would have to flash (replace) the firmware in the phone with a different firmware. This would also render the phone unusable on the Tracfone system. Reports indicate that phones unlocked by other methods will only work until the minute bank in the phone reaches zero, then it will no longer work.

Generally a sim card that has not had a phone number assigned to it will produce an "unregistered sim" message on the phone. All sims are unregistered until assigned a number and activated by a carrier. An active sim or previously active sim placed in another phone, other than the one it is locked to, will usually produce a "sim reject" message on the phone. Sometimes these messages remain on the screen constant and other times they only show momentarily, this depends on the phone. Usually you can't even access the menu to transfer contact information from an old sim to a new phone.

Tracfone and Net10 do not have their own cellular system in the US. They resell service provided by other carriers. the two gsm providers they use are At&t & T-Mobile. Each provider needs a different sim card to communicate with their system.

Currently their are 3 different sim cards used by Tracfone and Net10.  Two are used for service provided by At&t, and the third is used for service provided by T-Mobile.

The At&t cards are designated by C4 (Cingular) and the T-Mobile sim cards are designated by T5 (T-Mobile). 

The two At&t cards are basically the same except for storage capacity. The TFSIMC4 is the older sim card. The TF64SIMC4 is the newer card and has more storage capacity. Any cards received from Tracfone or Net10 now would probably be the newer card. The T-Mobile card is labeled TFSIMT5. These markings can be seen on the sim card without removing it from the phone. The sim card is located in the battery compartment underneath the battery.

I have also noticed 2 distinctions between the card serial numbers which will help to determine which card you have in your phone without having to remove the card or the battery.

To determine which carrier's sim card is packaged with a phone you can look for the model number on the sticker where the serial number bar code is for the phone. Phones packaged with At&t sim cards have P4 at the end of the model number, example TFC139P4. Phones packaged with T-Mobile sim cards have P5 at the end of the model number, example TFC139P5.

When transferring service from one phone to another the sim card in the new phone should be for the same service provider as the sim card in the old phone. If you are changing locations and the other provider has better service in that area you may want to switch from your current provider to the other.

If you want to transfer a phone number from a phone serviced by T-Mobile to a phone serviced by At&t, or visa versa, it is the same as porting a number from one company to another. Sometimes this can go very smooth and quick with Tracfone and Net10, other times it can be a pain and take several days to weeks.

If you are activating a phone online, and input the sim card number during the activation process, a previously used sim card will return a "not in system" result. You don't have to worry about this with new phones.

The system knows which carriers card was packaged with each serial number. During activation when you put in the serial number for the phone, and then put in a zip code, the system determines whether the sim card shipped with that serial number will work in the zip code provided. If it will, it usually doesn't ask for the sim card number and just proceeds with the activation process. If you used a sim card for a different carrier than the one packaged with the phone, and were not prompted to enter the sim card number, the system will still complete the activation process but your phone will not activate. It will probably continue to give a unregistered sim message. You will have to call tracfone and after them trying for a while to remedy the situation they will send you a new sim card.

If the system determines that the card shipped with the phone will not work in the area, the system will ask for the sim card number to make sure you have the proper sim card. If you provide a sim card number for a card that will not work with the carrier in that area the system will return a message telling you that they will need to send you a new sim card before you can continue with the activation process. If the sim number you provide is a correct one then the system will continue with the activation process and you will likely have no problems.

You can read some very in depth information on sim cards here.

What Kind of Information Is Stored on My SIM Card?

The following information is stored on your Subscriber Identity Module (SIM) card: