Recently, I was working on an IT Help Desk project where we had a column called ‘Support Comments‘ in a SharePoint list. The idea was simple: every time someone from the support team had an update, they would add a new comment. But here’s the tricky part: I didn’t want to overwrite or delete the old comments.
At first, I wasn’t sure how to manage this dynamically. After some research, I discovered the “Append to array variable” action in Power Automate. It turned out to be the perfect solution for collecting and storing multiple entries over time without overwriting any existing data.
In this tutorial, I will show you exactly how to use this action to append multiple values to an array in Power Automate.
Append to array variable Action
The “Append to array variable” action in Power Automate is used to add (append) a new item to an existing array variable. It doesn’t replace the old values; it simply adds the new item to the end of the array, making it very useful for building collections dynamically during a flow run.
It accepts two parameters:
- Name: The name of the array variable you want to append to (must be initialized earlier using “Initialize variable“).
- Value: The item you want to add (append) to the array can be a string, number, object, or even another array.
Example 1: Append New Training Topics to an Existing Task Array
Imagine you have initialized an array variable with a predefined task: “Leadership training”. As new training needs come in (for example, “Security training”), you want to dynamically add them to the array without overwriting existing values.
- Open Power Automate, click Create, and select Instant cloud flow. Choose ‘Manually trigger a flow’ as the trigger.
- Add an ‘Initialize Variable‘ action and provide the name of the variable varTasks, set the type as Array, and in the value parameter, provide below the array variable:
[
"Leadership training"
]
- Search for Append to array variable and add it, then give the below parameter:
- Name: varTasks
- Value: Provide the below string:
Security training
- Add a Compose action and provide the varTasks in the input parameter using dynamic content to display the array variable.
Now save the flow and run it manually. After the flow runs successfully, you can see that the “Security training” is appended to an array variable.
