Invalid Call Sign Requests

Last updated Thursday, August 27, 2026 6:39:39 AM (Arizona)
Thursday, August 27, 2026 1:39:39 PM (UTC)

Applications

Invalid Call Signs

This page shows the FCC guidelines for calls which are not available for requesting on an FCC application followed by the invalid call signs which have been requested in the last month and the rule they are in violation of.

The following call signs are not available for assignment and therefore any request for call signs in the following categories are invalid and will be denied.

  1. KA2AA-KA9ZZ, KC4AAA-KC4AAF, KC4USA-KC4USZ, KG4AA-KG4ZZ, KC6AA-KC6ZZ, KL9KAA- KL9KHZ, KX6AA-KX6ZZ;
  2. Any call sign having the letters SOS or QRA-QUZ as the suffix;
  3. Any call sign having the letters AM-AZ as the prefix (these prefixes are assigned to other countries by the ITU);
  4. Any 2-by-3 format call sign having the letter X as the first letter of the suffix;
  5. Any 2-by-3 format call sign having the letters AF, KF, NF, or WF as the prefix and the letters EMA as the suffix (U.S Government FEMA stations);
  6. Any 2-by-3 format call sign having the letters AA-AL as the prefix;
  7. Any 2-by-3 format call sign having the letters NA-NZ as the prefix;
  8. Any 2-by-3 format call sign having the letters WC, WK, WM, WR, or WT as the prefix (Group X call signs);
  9. Any 2-by-3 format call sign having the letters KP, NP or WP as the prefix and the numeral 0, 6, 7, 8 or 9;
  10. Any 2-by-2 format call sign having the letters KP, NP or WP as the prefix and the numeral 0, 6, 7, 8 or 9;
  11. Any 2-by-1 format call sign having the letters KP, NP or WP as the prefix and the numeral 0, 6, 7, 8 or 9;
  12. Call signs having the single letter prefix (K, N or W), a single digit numeral 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and a single letter suffix are reserved for the special event call sign system.
Call SignRule Violation
AA5RIC6.  Any 2-by-3 format call sign having the letters AA-AL as the prefix
AB5RIC6.  Any 2-by-3 format call sign having the letters AA-AL as the prefix
AC5RIC6.  Any 2-by-3 format call sign having the letters AA-AL as the prefix
AD5RIC6.  Any 2-by-3 format call sign having the letters AA-AL as the prefix
AE5RIC6.  Any 2-by-3 format call sign having the letters AA-AL as the prefix
AK1AME6.  Any 2-by-3 format call sign having the letters AA-AL as the prefix
AM1KI 3.  Any call sign having the letters AM-AZ as the prefix (these prefixes are assigned to other countries by the ITU)
AT0M  3.  Any call sign having the letters AM-AZ as the prefix (these prefixes are assigned to other countries by the ITU)
BE4TS Call does not fall within a valid group as per FCC Guidelines
GB7GV Call does not fall within a valid group as per FCC Guidelines
JU1CY Call does not fall within a valid group as per FCC Guidelines
K7LEOCCall sign is incorrectly formatted as per FCC Guidelines
KAZZCall sign is incorrectly formatted as per FCC Guidelines
KWAZCall sign is incorrectly formatted as per FCC Guidelines
 L4KA Call does not fall within a valid group as per FCC Guidelines
NA5RIC7.  Any 2-by-3 format call sign having the letters NA-NZ as the prefix
NB5RIC7.  Any 2-by-3 format call sign having the letters NA-NZ as the prefix
NC5RIC7.  Any 2-by-3 format call sign having the letters NA-NZ as the prefix
NFOPCall sign is incorrectly formatted as per FCC Guidelines
WC5RIC8.  Any 2-by-3 format call sign having the letters WC, WK, WM, WR, or WT as the prefix (Group X call signs)
WK8FOX8.  Any 2-by-3 format call sign having the letters WC, WK, WM, WR, or WT as the prefix (Group X call signs)
WK9FOX8.  Any 2-by-3 format call sign having the letters WC, WK, WM, WR, or WT as the prefix (Group X call signs)
WK9PUP8.  Any 2-by-3 format call sign having the letters WC, WK, WM, WR, or WT as the prefix (Group X call signs)
WL71Call sign is incorrectly formatted as per FCC Guidelines
WR0TTY8.  Any 2-by-3 format call sign having the letters WC, WK, WM, WR, or WT as the prefix (Group X call signs)