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Home Network Codes System ID Global Roaming Prepaid Roaming Travel Phones


System Identification Numbers, or SIDs, are numeric codes used by cellular systems to identify the home system of a wireless carrier and by the cellular phone to determine its roaming status. Our lists are updated as changes are discovered. Some entries are in the name of the legal office who represents a wireless company. In the US, cellular SID's were originally assigned and recorded by the FCC, but in 2003 they decided to privatize the function of assigning and recording cellular SIDs.

Entries with expiration dates may have been renewed.

Note: Some of these lists are large, but we have broken them into more download-friendly sizes.

Administration of Cellular SID's:
The administration of Cellular SID's was transferred from the FCC to the private sector in October of 2003. With the transfer of this responsibility, the SID was removed from the cellular license. Cellular licensees seeking a new SID assignment, an additional SID assignment, or that have ceased using an assigned SID, will be required to make their request / notification through one of the recognized SID Administrators to perform Cellular SID administration. Each organization will operate under the general guidelines developed by the FCC and the cellular industry.

The year 2000 biennial review of the Cellular Radiotelephone Service resulted in the Federal Communications Commission eliminating System Identification Numbers from its rules. This impacted cellular carriers in three ways:
  1. Cellular SID Administration would be transferred from the FCC to the private sector,

  2. The SID would no longer be a term of a cellular license.

  3. The FCC issued SID administrator guidelines outlining the responsibilities of each administrator and signed a Memorandum of Understanding with each recognized administrator.


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