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Unassigned call signs
Four-letter K and W calls nobody holds, by prefix.
Spotted a call you want? Verify it before filing.
The call sign search the FCC offers covers broadcast stations only. Our free Call Sign Check adds shortwave stations and FCC ship licenses, flags a call that was recently released or is moving to a new owner, and gives the rule behind each result.
In each box: the prefix, plus the count of its 676 combinations that are unused.
K call letters: west of the Mississippi River
- KA220
- KB203
- KC207
- KD354
- KE372
- KF366
- KG392
- KH343
- KI380
- KJ395
- KK356
- KL207
- KM284
- KN346
- KO334
- KP329
- KQ406
- KR187
- KS196
- KT209
- KU398
- KV359
- KW301
- KX365
- KY406
- KZ359
W call letters: east of the Mississippi River
- WA197
- WB176
- WC176
- WD310
- WE309
- WF314
- WG310
- WH263
- WI340
- WJ241
- WK133
- WL155
- WM174
- WN284
- WO380
- WP271
- WQ401
- WR147
- WS209
- WT242
- WU442
- WV311
- WW305
- WX376
- WY380
- WZ391
Freed up in the past 60 days
Given up by stations that took a new call sign or left the air. Once the change takes effect, anyone may reserve one (FCC 98-324, paragraph 16).
KWME KXTE KZLB KLSQ KVWG KMFR WBTK KCAF KIBL KWYU KUFA KBQQ KIBQ KQBQ WPLI WMON WWXL KQSX KVFR KQHM KGWT WAJP KOHM KPQG KXAM KHMJ KHMZ KEHM KAVL WLVP WXDR WTSD KCRQ KDAC KOWL WGOC KEVO WLLF WBTH WTYX WPOM WIME WGOP KCLW KUIK KMBS KBKG WYEJ WVMG WPBW KFTI WLLS WBNZ KBOQ WYRC KLDI WQAH KGNM
Ahead of filing
An apparently open call may still cause trouble: broadcast stations cannot take four-letter calls assigned to ships or other radio services (47 CFR 73.3550(k)), the Mississippi River divides K from W (73.3550(e)), and using a base call held by another station requires its consent first (73.3550(h), (m)). Our Call Sign Check reviews every one of these points for any call almost instantly.
Current to October 16, 2026, drawn from FCC records for stations, ships and shortwave, with a fresh update each morning. Not an FCC product.