Official

Skybox Name Map Credit Total
sky_day01_01 sky_day01_01
(HDR)
Itemtest · Target Valve 2
sky_tf2_04 sky_tf2_04
(HDR)
2Fort · Banana Bay · Byre · Cachoeira · Canaveral · Embargo · Megaton · Odyssey · Phoenix · Sunshine Valve 10
sky_upward sky_upward
(HDR)
Camber · Upward Valve 2
sky_dustbowl_01 sky_dustbowl_01
(HDR)
Background01 · Bigrock · Coal Town · Dustbowl (CP) · Dustbowl (TR) · Egypt · Fastlane · Gullywash · Steel · Turbine* Valve 10
sky_goldrush_01 sky_goldrush_01 Asteroid · Doomsday · Gold Rush · Hoodoo · Mossrock · Nucleus (ARENA) · Nucleus (KOTH) · Offblast · Ravine · Rotunda Valve 10
sky_granary_01 sky_granary_01
(HDR)
Granary (ARENA) · Granary (CP) · Overgrown · Selbyen · Vanguard · Yukon Valve 6
sky_well_01 sky_well_01
(HDR)
Cloak · Freight · Mannhattan · Sharkbay · Snakewater · Well (ARENA) · Well (CP) · Well (CTF) Valve 8
sky_gravel_01 sky_gravel_01
(HDR)
Foundry (CP) · Foundry (CTF) · Gravel Pit Valve 3
sky_badlands_01 sky_badlands_01 Badlands (ARENA) · Badlands (CP) · Badlands (KOTH) · Brickyard · Cactus Canyon · Decoy · Example · Galleria · Hardwood · Hightower · Mountain Lab · Snowplow Valve 12
sky_hydro_01 sky_hydro_01
(HDR)
Altitude · Applejack · Badwater Basin · Cascade · Enclosure · Frontier · Hellfire · Highpass · Hydro · Junction · Lakeside · Powerhouse · Tiny Rock · Venice Valve 14
sky_night_01 sky_night_01 Bread Space · Chilly · Coal Pit · District · Eyeaduct · Ghost Fort · Ghost Town · Gorge Event · Kong King · Lava Pit · Metalworks · Moldergrove · Pipeline Valve 13
sky_nightfall_01 sky_nightfall_01 Crasher · Double Cross · Frostcliff · Megalo · Nucleus (VSH) · Perks · Probed · Turbine Center Valve 8
sky_trainyard_01 sky_trainyard_01 5Gorge · Burghausen · Cashworks · DeGroot Keep · Gorge (CP) · Gorge (CTF) · Haarp · Landfall · Lumberyard · Process · Rottenburg · Suijin · Swiftwater · Watchtower Valve 14
sky_stormfront_01 sky_stormfront_01 Coldfront · Doublefrost · Emerge Valve 3
sky_morningsnow_01 sky_morningsnow_01 Barnblitz · Frostwatch · Rumford · Viaduct Valve 4
sky_alpinestorm_01 sky_alpinestorm_01 Mannworks · Nightfall · Sawmill (ARENA) · Sawmill (CTF) · Sawmill (KOTH) · Standin · Thunder Mountain (CTF) · Thunder Mountain (PL) · Timbertown · Wutville Valve 10
sky_harvest_01 sky_harvest_01
(HDR)
Harvest Valve 1
sky_harvest_night_01 sky_harvest_night_01 Cauldron · Gravestone · Harvest Event · Moonshine Event · Spineyard · Spookeyridge Valve 6
sky_halloween sky_halloween Atoll · Bloodwater · Ghoulpit · Hellstone · Krampus · Los Muertos · Mann Manor · Maple Ridge Event · Soul-Mill Valve 9
sky_halloween_night_01 sky_halloween_night_01
(HDR)
Brimstone · Cursed Cove · Erebus · Helltower · Laughter · Murky · Pit of Death · Sandcastle · Sinshine Valve 9
sky_halloween_night2014_01 sky_halloween_night2014_01
(HDR)
Carnival of Carnage · Sinthetic · Terror Valve 3
sky_island_01 sky_island_01 Mercenary Park Valve 1

*This map uses the HDR skybox.

Community

These are NOT included in TF2 by default, and you'll have to ask the creators for permission to use them.

Skybox Name Map Credit Total
sky_jungle_01 sky_jungle_01 Borneo · Brazil Heyo 2
sky_invasion2fort_01 sky_invasion2fort_01 2Fort Invasion Neodos 1
sky_stormfront_02 sky_stormfront_02 SnowVille FubarFX 1
sky_well_02 sky_well_02
(HDR)
Watergate* Egan 1
sky_outpost_01 sky_outpost_01 Snowfall · Snowycoast E-Arkham 2
sky_coastal_01 sky_coastal_01 Lazarus Void 1
sky_frankenstorm_02 sky_frankenstorm_02 Hassle Castle Smiley the Smile 1
sky_midnight_01 sky_midnight_01 Slasher Void 1
sky_midnight_02 sky_midnight_02 Monster Bash · Snowtower · Woods Void 3
sky_volcano_01 sky_volcano_01 Precipice TanookiSuit3 1
sky_halloween_night_02 sky_halloween_night_02
(HDR)
Pier* Blade x64 1
sky_farmageddon_01 sky_farmageddon_01 Farmageddon Blaholtzen 1
sky_trainyard_night_01 sky_trainyard_night_01 Bonesaw · Graveyard Diva Dan 2
sky_northpole_01 sky_northpole_01 Polar Panckakebro 1
sky_halloween_02 sky_halloween_02 Helltrain Panckakebro 1
sky_frosty_01 sky_frosty_01 Frosty Emoglobinsky 1
sky_fuji sky_fuji Reckoner · Sulfur YM 2
sky_yuki_01 sky_yuki_01 Pelican Peak Void 1
sky_earlymorning_02 sky_earlymorning_02 Brew · Distillery Void 2
sky_triage_01 sky_triage_01 Skirmish Void 1
BrineEventSky_02 BrineEventSky_02 Slime Blaholtzen 1
sky_mannsylvania sky_mannsylvania Mannsylvania Phe 1
sky_stranded_01 sky_stranded_01 Corruption Panckakebro 1
sky_night_02 sky_night_02 Carrier · Devastation Void 2
sky_darkfog_01 sky_darkfog_01 Sanitarium Panckakebro 1
sky_hacksaw_01 sky_hacksaw_01 Hacksaw Diva Dan 1
sky_hadal_01 sky_hadal_01 Hadal FubarFX 1

*This map uses the HDR skybox.

No Skybox

If a map doesn't have a skybox set, by default the game will output this name, which is a non-existing skybox.

Skybox Name Map Credit Total
sky_urb01 sky_urb01 Atom Smash --- 1

Pyrovision

Skybox Name Map Credit Total
sky_pyroland_01 sky_pyroland_01 Doomsday · Gold Rush Valve 2
sky_pyroland_02 sky_pyroland_02 2Fort Valve 1
sky_pyroland_03 sky_pyroland_03 Badlands (ARENA) · Badlands (CP) · Badlands (KOTH) · Hightower · Viaduct Valve 5

Cut / Unused

Skybox Name Notes Credit Total
sky_tf2_05 sky_tf2_05 Not included in the game files Valve 0
sky_tf2_06 sky_tf2_06 Not included in the game files Valve 0
sky_rainbow_01 sky_rainbow_01 Probably an early verion of sky_pyroland_03 Valve 0
sky_badlands_pyroland sky_badlands_pyroland It was going to be used in Hightower, and given the name of the skybox, it was probably the one used instead of sky_pyroland_03 Source Valve 0

Note: The ones in bold are the first ones to use that skybox.