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  • Actuator item spriteold Actuator item sprite
Stack digit 9Stack digit 9Stack digit 9Stack digit 9
Use time15 (Very fast)
TooltipEnables solid blocks to be toggled on and off
RarityRarity level: 0
Research50 required

The Actuator is a mechanism item purchased from the Mechanic for 10 each, or harvested from sand, lava, or Dead Man's Chest traps. It has to be connected with wiring to function. When activated, the tile it is on toggles between active and inactive state, effectively allowing any block to be toggled like active or inactive stone blocks. Like wire, Actuators are normally invisible and only become visible when a mechanism item is selected.

The following items interact with Actuators:


Used in[]

ResultIngredientsCrafting station
Actuation RodActuation Rod
Iron AnvilIron Anvil
Lead AnvilLead Anvil


  • In addition to most blocks and traps, Actuators can also activate on teleporters and platforms.
  • Most furniture on top of a block/platform with an actuator will be freed when the actuator activates.
  • Actuators won't activate if they are directly beneath a tree, Demon Altar, Crimson Altar, Lihzahrd Altar, or any chest (regardless of whether it contains items or not). This block actuator protection is present on the 2nd layer of blocks under a chest as well (4 blocks total).
  • Any plants growing on a block which is put into its inactive state by an actuator will be destroyed as if a tool was swung at it. This can be used to harvest mushroom farms. Herbs, however, will remain on the inactive block.
  • Liquids and falling blocks like sand, silt and slush can pass through blocks which an actuator has made inactive. On the Old-gen console version Old-gen console, Windows Phone version Windows Phone, Old Chinese version Old Chinese, 3DSNintendo 3DS version, and tModLoader 1 tModLoader Legacy versions, falling blocks won't pass through.
  • Inactive Biome blocks will still count towards the formation of their respective biomes.
  • Naturally occurring Lihzahrd Bricks cannot be actuated until Plantera has been defeated.
    • This was originally possible by intention, because Biome Keys previously did not drop directly and required a Temple Key to craft. This was changed in 1.2 to remove the Biome Key Mold items, and in turn the need to consume Temple Keys.
  • NPCs can spawn on top of actuated blocks and thus fall through them.
  • Inactive blocks do not count as walls for NPC housing, so a house with actuated blocks making up any of its walls will become invalid.
  • In the Console version Console version, the locked Jungle Temple door is able to be actuated.
  • Portal Gun's Portals, if placed before the blocks are actuated, will not vanish and will still function normally.
  • Actuators have no effect on bubbles.


  • Using Actuators in place of doors creates entrances that can completely block off the enemies from a Blood Moon or other events.
    • It is also possible to make an airlock-type double door system using 6 Actuators and activating only one side inactive/active. This, combined with a trigger of your choice, will allow access for players only while keeping a house. You still need a door or some platforms for housing purposes, but this style of door can be put on outer NPC housing directly to conserve any expensive materials your house is made of.
  • Because they work on traps, it is possible to load up several traps in a row, and none of their attacks will be blocked by traps ahead.
  • Actuators can be used to pass through Hellstone in the Underworld without generating lava, and can similarly be used to pass through hive blocks without generating honey or spawning bees. The Actuation Rod may be used to quickly activate placed Actuators.
  • If you stand inside an inactive block and it becomes active, you will be able to move inside the 6 blocks you are in but will be stopped by other blocks. This may be used for protection.
  • Like naturally-generated wires, naturally-generated Actuators can be harvested, though they appear much more rarely, saving 10 per Actuator.
  • Actuators are a good tool for terraforming/clearing the way for a plot, especially underground.


  • The Multicolor Wrench is not capable of removing Actuators, even though it is crafted using the Wire Cutter, which does remove Actuators.
    • However, the Grand Design, crafted from the Multicolor wrench, is capable of doing so.


  • Desktop 1.2.4: Actuated tiles no longer remove the water over them on world load.