2026.6.4
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Set variable value

Use this action to set the value of a system variable on your CCU or Homegear.

Using this action from the user interface

If you prefer building automations and scripts visually, Home Assistant walks you through this action step by step. You pick what to target, tweak a few options, and save. No YAML knowledge required.

To set a variable value from an automation or a script:

  1. Go to Settings > Automations & scenes.
  2. Open an existing automation or script, or select Create automation > Create new automation.
  3. If you’re setting up a new automation, add a trigger in the When section. Scripts don’t need a trigger. They run when something else calls them.
  4. In the Then do section, select Add action.
  5. From the search box, search for and select Homematic: Set variable value.
  6. Enter the variable Name and the new Value and, optionally, choose an Entity.
  7. Select Save.

This action does not support targets. In the UI, you are not prompted to choose an area, device, entity, or label. To set the variable on a specific Homematic hub, use the Entity field instead. When you leave it empty, the variable is set on all hubs.

Options in the UI

Name (Required)

The name of the variable to set.
Value (Required)

The new value for the variable.
Entity

One or more Homematic hub entities to set the variable on. Defaults to all hubs.

Using this action in YAML

If you work directly in YAML, or you want to know exactly what Home Assistant does under the hood, this section has the technical reference. It lists the field names you use in YAML, their types, and which ones are required.

In YAML, refer to this action as homematic.set_variable_value:

ActionActions are used in several places in Home Assistant. As part of a script or automation, actions define what is going to happen once a trigger is activated. In scripts, an action is called *sequence*. [Learn more] 
action: homematic.set_variable_value
data:
  name: "Variablename"
  value: true
  entity_id: homematic.ccu2

Options in YAML

name string Required

The name of the variable to set.

value any Required

The new value for the variable.

entity_id string | list

One or more Homematic hub entities to set the variable on. Defaults to all hubs.

Try it yourself

Ready to test this? Open Developer tools > Actions, search for this action, fill in the fields, and select Perform action. You see what happens on your actual entitiesAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more] without writing a line of YAML.

Still stuck?

The Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with the action you’re calling and what you expected to happen, or share on our subreddit /r/homeassistant.

Tip

AI assistants like ChatGPT or Claude can also explain actions or suggest the right one when you describe what you want in plain language.

Related actions

These actions work well alongside this one:

  • Set device value: Controls a Homematic device manually using its setValue method.

  • Virtual key: Simulates a keypress on a Homematic device or virtual remote.

  • Put paramset: Manually changes a Homematic device’s paramset using its putParamset method.

  • Reconnect: Reconnects to all Homematic hubs.

  • Set install mode: Sets a Homematic XML-RPC interface into installation mode.