While an attempt has been made to be as comprehensive as possible in the Science Fiction Index, a line had to be drawn somewhere and there are a number of titles you might expect to find here which have been deliberately excluded. These fall into three major categories:
The original index compiled by Stephen T. Miller and William G. Contento was created at a time when few other "genre" indexes had been written and, as such, indexed a number of "fringe titles", particularly in the "hero pulp" and "weird menace" fields, which has some elements of SF but do not really qualify as science fiction, fantasy or weird fiction. As these have now been fully indexed elsewhere, particularly in the Crime Fiction Index and the Adventure Fiction Index there seems no need to repeat them in this index. The titles concerned are:
The original index also contained a number of magazines which typically contained little or no SF, but which published special SF issues, or which had some related connection to the genre. In many cases other issues of the same magazine are already indexed in the Fictionmags Index so it seems sensible to exclude those magazines from this index as well. The titles concerned are:
The SFFWF field is an incredibly prolific one and there are (literally) an unknown number of minor magazines, ranging from the fanzines of the 1930s to the online magazines of the 2010s, many of which have not even been catalogued, let alone indexed. In some cases, partial listings of these titles are available in the Fictionmags Index while in others little is known beyond the magazine title and rough publication details. Over time, hopefully, some of these titles will be fully indexed and will be added to the Science Fiction Index, but, for now, the following titles have been excluded:
| Abortions | Dragons, Knights and Angels | Janus | Renaissance |
| Absent Willow Review | Dragonwings | Jayland Unlimited | Revolution Science Fiction |
| Ad Astra [1965] | The Dream Cell | Jinnia Clan Journal | The Richard S. Shaver Magazine |
| Adbhut | Dream Quest | Jinx | Rictus |
| Afterburn SF | Dream Scene | Kasma SF Magazine | Schlock! Webzine |
| Agog | Duckspeak | Kenoma | Science*Fiction [1945] |
| Aleph-Null | Ecce | Kinda Kinky | Science Fiction Scout |
| Alien Culture | Eclipse [1966] | Klein Bottle | Scienti-Comics |
| Alien Landings | Eclipse [1970] | Knights | Scifaikuest |
| Alien Skin | Edge of Twilight | The Kore | SciFi Dimensions |
| alphaDrive | eFantasy | Labyrinth Inhabitant | SciFi Freedom |
| Altair [1950] | Eldritch Science | Lakeside Circus | SciFi Paradox |
| Altered Reality | Electric Wine | Laser & Sword Magazine | Sci-Fi Short Story Magazine |
| Alternate Realities | Elegia | Lathered in Crimson | Scorched Earth |
| Alternaties | 1130 Club | Laughing Osiris | Scream Queens Illustrated |
| Alternative Coordinates | Embelyon | Leprechaun | SDO Fantasy |
| Anomaly | Empire for the SF Writer | Les Spinge | Senary |
| Anotherealm | Entropy | Lethe | Sentinel SF |
| Antares | Erotic Horror & Fantasy Magazine | Lighthouse [1960s] | Seventh Dimension |
| Anthro | Escape [1930s] | The Little Corpuscle | The Seventh Seal |
| Antithesis [1973] | Escape Velocity | The Looking Glass | Severed Tales |
| Apocalypse Fiction | Eternity | Lost Pages | SFanzine |
| Appalling Stories | Ethereal Gazette | Lost Worlds | Shadowdance |
| Arcana | Eulogy | Lovecraftiana | Shadowland [1950s] |
| Arioch | Eusifanso | Low Orbit | Shadowland [1990s] |
| Art & Story | Event Horizon [1987] | Lunar Castles | Shiver |
| ASFO | Exile [1960s] | Macabre Tales | Silver Blade |
| Asmodeus [1969] | Expressions of Dread | Mad Scientist Journal | Sinfully Twisted |
| Astonishing Stories [1935] | Extro [1980] | Mainstream | Sinister Tales |
| Astounding Tales | Eye of Newt | The Many Worlds of Jack Vance | Skewed |
| Athene | Eye to the Telescope | Maplecade | Sky Hook |
| Atomjack | Fadaway | Marginal Boundaries | S1ngularity |
| Aurora Speculative Feminism | Fairy Tale Review | Mars! | The Sockdolager |
| Auslander | Fanatic | The Marvellous Magazine | Sol Reader |
| Avatar | Fandom Unlimited | The Masked Spaceman | Sonar4 |
| Avesta | Fanomena | Masque (UK) | The Southern Star |
| Banana Skins | Fan Slants | Meshuggah | Space Gamer/Fantasy Gamer |
| Banana Wings | Fantasia [1941] | Midnight Wine | Spaceports and Spidersilk |
| Bane | Fantasia [1951] | Mindflights | Space Squid |
| The Banshee | Fantasite | Mindscapes | Spacesuits and Sixguns |
| Barbarian Scroll | Fantast Sidetrack | Mirage | Space Tales |
| Bardic Runes | Fantasy Annual [1948] | Miriad | Spaceteer |
| The Barsoomian | Fantasy Collector's Annual | Mirth and Irony | Spaceways [1996] |
| Bar Trek | Fantasy Digest | The Miskatonic | Spearhead |
| Basement Stories | Fantasy Fiction Field | Modern Mythology | Spectra-Foundation SF & Fantasy Mag |
| Beabohema | Fantasy Jackpot | Monomyth | Spectra Magazine |
| Betelgeuse | Fantasy Times | The Monsters Next Door | Speculation |
| Bête Noire | Fantazone | Moondust | Speculative Fiction and Beyond |
| Bewildering Stories | Fanvariety | Morgan Smith | Speculon |
| Beyond [1943] | Farrago | Moslem in Cambridge | The Specusphere |
| Beyond the Moon | Fear and Trembling Magazine | The Multiversal Scribe | SPGA Showcase |
| Bite Me Magazine | FemSpec | Multiverse Magazine | Staffs and Starships |
| Black Flames | Fiction Inferno | Muse Fantastique | The Stake |
| Black Hole | Fifth Di... | Muzzy | The Standing Stone |
| The Black Lily | Flapperhouse | Mythos | Stardust [1960s] |
| Black Moon | Flash Fantastic! | The NASFA Shuttle | Starlight |
| Black Oracle | Flashing Swords | Nebula [1950] | Starlit Fantasy |
| Black Skull Magazine | Fogfire | Nebula [1970] | Steampunk Tales |
| Blood from 'Stones | Foma | Necrography | Stellarite |
| Bloodlines | Fools Motley Magazine | Necrophantasy | STFanatic |
| Bloodrake | Fortean Bureau | Neometropolis | Stone Telling |
| The Blue Lady | Foundation | Neverary | Straitjacket |
| Bone Chilling Tales | Foxfire | Neverworlds | Strange Aeons [1990s] |
| Bone Marrow Review | Franson's | New Realm | Strange Aeons [2010] |
| Brillig | Freedom Fiction Journal | New Venture [1975] | Strange Brew |
| Bulletin of Terrestrial Fantascience Guild | F(r)iction | New Witchcraft | Strange, Weird and Wonderful Magazine |
| Burroughs Bulletin | FTL Science Fiction | New Words | Strix |
| Byzarium | Full Moon S.F. | Next Phase | The Stylus [1993] |
| Cabal Asylum | Fusion Fragment [2007] | Nexxus | Sun Spots |
| Cactus | Future Focus | Night Dreams | Surprising Stories |
| Camber | Futurian War Digest | The Nightmare Express | The Sword Review |
| Canadian Fandom | Futurismic | Nightmares Quarterly | Swords and Sorcery Magazine |
| Canticles from Labowitz | Garage Floor | Nightside | Symphonie's Gift |
| Catenary Tales | Gathering Darkness | Night Views | Syzygy |
| Cats with Wings | Gauntlet! The Magazine of Heroic Tales | Nightworld | Tabebuian |
| Cemetery Moon | genrEzone | Niteblade | Talers Tales |
| Centauri | Giallar | The Nocturnal Lyric | Tales from Texas |
| Challenger | Glutonlumps Chilling Tales | Nomad | Tales of Blood and Roses |
| Chanticleer | Goblin Fruit | Not at Night | Tales of Horror and Damnation |
| Chaos Theory: Tales Askew | Golana | Nova [1941] | Tales of the Episco Pals |
| The Chigger Patch of Fandom | Golden Atom | Nova [1972] | Tales of the Grotesque and Arabesque |
| Chimaeran Review | Golden Visions Magazine | Nova [1989] | The Tale Spinner |
| Chronicle | Goodwitch Stories | Novae Terrae | Tangent [1976] |
| Ciln | Gothic Light | The Nucleus | Terraform |
| Cinquefoil | Granfalloon | Nuketown | Terror |
| Citadel | Graveyard Rendezvous | Nu Ormenel Collected | Terror Hunters Journal |
| The City Morgue | Grimoire [1993] | Odd Tales of Wonder Magazine | The Thing |
| Clarges | Grok | Of Unicorns and Space Stations | Third Order |
| The Comet (fnz) | The Grotesque [1940s] | Ogre | Thirteen Magazine |
| The Communicator | Grue [1953] | Old Bones | This Way Up |
| Concept Sci-fi E-zine | Gryffon's Star | Omnifan | Tiamat |
| Cosmic Speculative Fiction | Grymalkin | Omni Online | TiconderogaOnline |
| Coyote Wild | Gryphonwood | The Oracle [1982] | Time Travel Tales |
| Crabapple | Hands in the Dark | Orion Science Fiction | Tiofart |
| Crifanac | Harbinger [1975] | The Orphic Chronicle | TLMA |
| Cyberpulp Magazine | The Hardcore | Ouroboros | Tomorrow Magazine [1970] |
| Cygni | Harsh Reality | The Outlander | Toward Tomorrow |
| The Cygnus Chronicler | Haunted Journal | Outside | Tower of Light |
| The Daily Phantagraph | Heart Attack | Outsider | Trail of Indiscretion |
| Damned Thing | Heliocentric Net | Pages [1988] | Troat |
| Dark Energy | Heliophobe | Pan Demos | The Tryout |
| Dark Infinity | Hocus | Pantechnicon | TSAT (Transformation Stories) |
| Dark Moon Rising | Holier Than Thou | Papyrus [1999] | Twilight Garden |
| Dark Muse | Horizons (fnz) | Paradox [1942] | Twilight Times |
| Dark's Art Parlour | Horrorfest | Parageography | Twin Cities SF & Fantasy Magazine |
| Dark Side | The Horror Fiction Review (fnz) | Parlour Papers | Twisted Dreams Magazine |
| Dark Star | The Horror Zine | Pegasus Online | Ultraverse |
| Dark Tome | The H.P. Lovecraft Fanzine | Peridot Books | Undinal Songs |
| Dark Visions | Hugin and Munin | The Periodical Lungfish | Universe Pathways |
| Darwin's Evolutions | Hyphen [1952] | Phantasia | Usok |
| Daughters of Nyx | Ibidem | Phenomena | Utopian |
| Dead Letters | Ibn Qirtaiba | Phile | Vamperotica Magazine |
| Deadspawn | If! (fnz) | Piffle | The Vampire Journal |
| Demensions | IFA Review | Planet Magazine | Vanations |
| Dementia 13 | Illumen | Planet Relish | The Velvet Vampyre |
| Descend | Imagination [1971] | Pluto | Visionary Tongue |
| Destiny [1991] | Imagination [1990s] | Polaris [1980] | Vortex Temporum |
| Dianoura | Imaginative Fiction | Polluto | Waxen Wings and Banana Skins |
| Diaspar | Incredible | Popular Music & Science-Fiction Journal | Weird Space |
| Diehard | Infinite Edge | Pornographic Onion | Whispers from the Dark |
| A Different Path | Infinity [1970] | Port Iris | White Dwarf |
| Digital Catapult | Infinity [1987] | Procyon | White Wolf |
| Digital Dragon | Infinity Ltd. | Proteus [1966] | The Wolverine |
| Digressions | Inside (Science Fiction) | Psychic Dimensions | Wotta World |
| Dipple Chronicle | Interstellar Fiction | Pulsar! | Would That It Were |
| Distant Worlds | InterText | Quantum | Yandro |
| Don-o-saur | In the Shadow of the Monolith | Quantum Kiss | Yawning Vortex |
| Doorways | Invisible Stories | Quantum Muse | Ye Yowlings of Yog-Sothoth |
| Double:Bill (fnz) | Is | Radius | Zenith (Speculation) |
| Dragonlaugh | Ixxis | Realm of Fantasy | The Zobee |
| Dragonlore | Jackhammer E-zine | Redshift |