Federation Members
Listed in order of joining:
- United Earth
- Joined: August 12, 2161
- Confederacy of Vulcan
- Joined: August 12, 2161
- Andorian Empire
- Joined: August 12, 2161
- Withdrew: 2382
- Rejoined: 2385
- United Planets of Tellar
- Joined: August 12, 2161
- Alpha Centauri Concordium
- Joined: August 12, 2161
- Confederated Martian Colonies
- Joined: 2162 (ENT Novel: A Choice of Futures)
- Vega Colony
- Joined: 2164 (ENT Novel: Tower of Babel)
- Former United Earth colony
- United Worlds and Colonies of Rigel
- Joined: 2164 (ENT Novel: Tower of Babel)
- Arken II
- Joined: Early 2165 (ENT Novel: Uncertain Logic)
- Former Andorian Empire subject world
- Ithen
- Joined: October 2165 (ENT Novel: Patterns of Interference)
- Risian Hedony
- Joined: late 22nd Century
- Camor V
- Joined: By 2200s (TNG Novel: Genesis Wave, Part I)
- Deltan Union
- Joined: By 2200s (TNG Novel: Genesis Wave, Part I)
- Trill
- Joined: By early-23rd Century
- Argelius
- Joined: 2240s/2250s (TOS Novel: Burning Dreams)
- Valzhan
- Joined: By mid-23rd Century
- Axanar
- Joined: After 2251, by 2260s
- Alpha Proxima II
- Joined: By 2260s
- Former United Earth colony
- Altair Colony
- Joined: By 2260s
- Former United Earth colony
- Arcturus
- Joined: By 2260s
- Plutocracy of Ardana
- Joined: By 2260s
- Withdrew: 2269
- Rejoined: By 2370s
- Aurelia
- Joined: By 2260s
- Cait
- Joined: By 2260s
- Irregular participation
- Cygnet
- Joined: By 2260s
- Denobula
- Joined: By 2260s
- Izar
- Joined: By 2260s
- Former United Earth colony
- Makus III
- Joined: By 2260s
- Medusan
- Joined: By 2260s
- Ramatis III
- Joined: By 2260s
- Regulus
- Joined: By 2260s
- Sauria
- Joined: By 2260s
- Scoridia
- Joined: By 2260s
- Sulamid
- Joined: By 2260s
- Tiburon
- Joined: By 2260s
- People's Republic of Coridan
- Joined: 2267
- Janus VI
- Joined: After 2267
- Aaamazzara
- Joined: By 2270s
- Betelgeusian Argosies
- Joined: By 2270s
- Kazar
- Joined: By 2270s
- Rhaandarel
- Joined: By 2270s
- Zaranai
- Joined: By 2270s
- Lorina
- Joined: After 2273 (TOS Novel: Ex Machina)
- Bole
- Joined: By 2280s
- Efros
- Joined: By 2280s
- Kashet
- Joined: By 2280s
- Kyppr
- Joined: By 2280s (VOY Novel: Acts of Contrition)
- Pacifica
- Joined: By 2280s (implicit by TNG Novel: Genesis Wave, Part I)
- Huan
- Joined: 2293
- Betazed
- Joined: By 2300s (TLE Novel: Cast No Shadow)
- Vestios
- Joined: 2310 (TOS Novel: Burning Dreams)
- Beta Antares IV
- Joined: By 2311
- Lorillia
- Joined: After 2311, By 2381
- Deneva
- Joined: By early-24th Century
- Former United Earth colony
- Gnala
- Joined: By early-24th Century
- Pythagos Clans
- Joined: By early-24th Century
- Tandar Prime
- Joined: By 2320s
- Zalda
- Joined: 2330s-2340s
- Alonis
- Joined: 2336
- Kerovi
- Joined: c.2340
- Oriki
- Joined: 2340s-2350s
- Candelar IV
- Joined: 2350s
- Cestus III
- Joined: By mid-24th Century
- Former Federation colony
- Dedderei
- Joined: By mid-24th Century
- Elas
- Joined: By mid-24th Century
- Gemworld
- Joined: By mid-24th Century
- Grazer
- Joined: By mid-24th Century
- Guidon Pontificate
- Joined: By late-24th Century
- Hermat Directorate
- Joined: By mid-24th Century
- Magna Roma
- Joined: By mid-24th Century
- Preserver transplant world
- Ochat
- Joined: By mid-24th Century
- Pandril
- Joined: By mid-24th Century
- Peliar Zel
- Joined: By mid-24th Century
- Selene
- Joined: By mid-24th Century
- Sigma Iotia II
- Joined: By mid-24th Century
- Tessen III
- Joined: By mid-24th Century
- Troyius
- Joined: By mid-24th Century
- Xindi Diaspora
- Joined: By mid-24th Century
- Pahkwa
- Joined: 2360
- Bynaus
- Joined: After 2364, by 2374 (TNG: "11001001"; SCE Short Story: "10 is Better Than 01")
- Benzar
- Joined: After 2365, by 2374
- Damiano
- Joined: 2371
- Lendrin
- Joined: After 2371, by 2378
- Andros III
- Joined: By late-24th Century
- Antede III
- Joined: By late-24th Century
- Arbaza
- Joined: By late-24th Century
- Asario
- Joined: By late-24th Century
- Atrea IV
- Joined: By late-24th Century
- Bilana III
- Joined: By late-24th Century
- Bre’el IV
- Joined: By late-24th Century
- Cairn
- Joined: By late-24th Century
- Caldos II
- Joined: By late-24th Century
- Former Federation colony
- Carnegie
- Joined: By late-24th Century
- Former Federation colony
- Commonwealth of Denebia
- Joined: By late-24th Century
- Delb II
- Joined: By late-24th Century
- Delta Sigma IV
- Joined: By late-24th Century
- Gallamite
- Joined: By late-24th Century
- Grilasdixraksirvek
- Joined: By late-24th Century
- Hekaras II
- Joined: By late-24th Century
- Icor IX
- Joined: By late-24th Century
- Inferna Prime
- Joined: By late-24th Century
- Ktar
- Joined: By late-24th Century
- Meldrar I
- Joined: By late-24th Century
- Napea
- Joined: By late-24th Century
- Nasat
- Joined: By late-24th Century
- Parnasi
- Joined: By late-24th Century
- Pentam V
- Joined: By late-24th Century
- Triex
- Joined: By late-24th Century
- Tyrellia
- Joined: By late-24th Century
- Ysa
- Joined: By late-24th Century
- Zakdorn
- Joined: By late-24th Century
- Zanri
- Joined: By late-24th Century
- Ontail
- 152nd member
- Joined: Mid-2373 (TNG Novel: A Time to Be Born)
- Evora
- 153rd member
- Over 150 members by October 2373 (Star Trek: First Contact)
- Joined: 2375
- 153rd member
- Third Republic of Bajor
- 154th member
- Joined: September 29, 2376
- Koa
- 155th member (Novel: Articles of the Federation)
- Joined: 2380