Invalid Call Sign Requests

Last updated Tuesday, April 7, 2026 5:56:50 AM (Arizona)
Tuesday, April 7, 2026 12:56:50 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
A1A1Call sign is incorrectly formatted as per FCC Guidelines
A2A2Call sign is incorrectly formatted as per FCC Guidelines
ALPHA1Call sign is incorrectly formatted as per FCC Guidelines
B1B1Call sign is incorrectly formatted as per FCC Guidelines
BRAVO1Call sign is incorrectly formatted as per FCC Guidelines
DN2A  Call does not fall within a valid group as per FCC Guidelines
FFKFCall sign is incorrectly formatted as per FCC Guidelines
K1K1Call sign is incorrectly formatted as per FCC Guidelines
KNCT951Call sign is incorrectly formatted as per FCC Guidelines
LOVE1Call sign is incorrectly formatted as per FCC Guidelines
NC7CRD7.  Any 2-by-3 format call sign having the letters NA-NZ as the prefix
NK7CRD7.  Any 2-by-3 format call sign having the letters NA-NZ as the prefix
PZ3WENCall does not fall within a valid group as per FCC Guidelines
PZ7WENCall does not fall within a valid group as per FCC Guidelines
T1T1TCall sign is incorrectly formatted as per FCC Guidelines
TANGOCall sign is incorrectly formatted as per FCC Guidelines
TANGO1Call sign is incorrectly formatted as per FCC Guidelines
TC5BEPCall does not fall within a valid group as per FCC Guidelines
TOM1Call sign is incorrectly formatted as per FCC Guidelines
TTAT1Call sign is incorrectly formatted as per FCC Guidelines
USA0Call sign is incorrectly formatted as per FCC Guidelines
USA1Call sign is incorrectly formatted as per FCC Guidelines
USA2Call sign is incorrectly formatted as per FCC Guidelines
USA3Call sign is incorrectly formatted as per FCC Guidelines
USA4Call sign is incorrectly formatted as per FCC Guidelines
USA5Call sign is incorrectly formatted as per FCC Guidelines
USA6Call sign is incorrectly formatted as per FCC Guidelines
USA7Call sign is incorrectly formatted as per FCC Guidelines
USA8Call sign is incorrectly formatted as per FCC Guidelines
USA9Call sign is incorrectly formatted as per FCC Guidelines
VVAVCall sign is incorrectly formatted as per FCC Guidelines
W0WU,Call sign is incorrectly formatted as per FCC Guidelines
WOW1Call sign is incorrectly formatted as per FCC Guidelines
WT6JSL8.  Any 2-by-3 format call sign having the letters WC, WK, WM, WR, or WT as the prefix (Group X call signs)
WT6ZSL8.  Any 2-by-3 format call sign having the letters WC, WK, WM, WR, or WT as the prefix (Group X call signs)