After running a custom PowerShell script in Power Automate Desktop, how do I capture the output into a new variable?

I’m using Power Automate Desktop and running a custom PowerShell script using the "Run PowerShell Script" action.

Here is the PowerShell script I’m using:

# Get the 1st day of the current month
$now_date = Get-Date -Day 1 -Month (Get-Date).Month -Year (Get-Date).Year -Format "dd-MMM-yy"

# Get the last day of the current month
$month_after = (Get-Date -Day 1 -Month (Get-Date).Month -Year (Get-Date).Year).AddMonths(1).AddDays(-1) -Format "dd-MMM-yy"

# Initialize variables for the previous month's 1st and last days
$prev_month_first = $null
$prev_month_last = $null

# Check if now_date and month_after are the same
if ($now_date -eq $month_after) {
    # Calculate the 1st day of the previous month
    $prev_month_first = (Get-Date -Day 1 -Month (Get-Date).AddMonths(-1).Month -Year (Get-Date).AddMonths(-1).Year) -Format "dd-MMM-yy"

    # Calculate the last day of the previous month
    $prev_month_last = (Get-Date -Day 1 -Month (Get-Date).Month -Year (Get-Date).Year).AddDays(-1) -Format "dd-MMM-yy"
}

# Output the values
$now_date, $month_after, $prev_month_first, $prev_month_last

In Power Automate Desktop:

The entire output goes into the %PowerShellOutput% variable.

I want to extract each of the four values ($now_date, $month_after, etc.) and store them into separate variables like %NowDate%, %MonthAfter%, etc.

I tried referencing %now_date% directly but it doesn’t work.

I’m okay with receiving the output as plain text — I just need a way to split it and store it properly.

Question: How do I parse the output of a PowerShell script into multiple new variables in Power Automate Desktop?

Is there a reliable method to separate the values from %PowerShellOutput% and assign them to individual variables?

Thanks in advance!

Your Script produces errors and thus returns a blank.

Enable the ScriptError variable under the variables produced options.

There are other errors in your script:

The script should be this:

# Get the 1st day of the current month
$now_date = Get-Date -Day 1 -Month (Get-Date).Month -Year (Get-Date).Year -Format "dd-MMM-yy"

# Get the last day of the current month
$month_after = Get-Date -Day 1 -Month (Get-Date).AddMonths(1).Month -Year (Get-Date).Year -Format "dd-MMM-yy"

# Initialize variables for the previous month's 1st and last days
$prev_month_first = $null
$prev_month_last = $null

# Check if now_date and month_after are the same
if ($now_date -eq $month_after) {
    # Calculate the 1st day of the previous month
    $prev_month_first = Get-Date -Day 1 -Month (Get-Date).AddMonths(-1).Month -Year (Get-Date).Year -Format "dd-MMM-yy"    
    #calculate last day of month
    $last_days_in_month = [DateTime]::DaysInMonth((Get-Date).Year, (Get-Date).AddMonths(-1).Month)
    # Calculate the last day of the previous month
    $prev_month_last =  Date -Day $last_days_in_month -Month (Get-Date).AddMonths(-1).Month -Year (Get-Date).Year -Format "dd-MMM-yy"
}
# Output the values
$now_date, $month_after, $prev_month_first, $prev_month_last

Get your script to run correctly in PowerShell, when I tested your script in Windows PowerShell ISE I got the same errors.

Once your script passes you will see the output in %PowershellOutput% this will be a multiline string, so you could use the Split Text action in power automate desktop to get a list, after which you can get the values according to the index in TextList variable.

copy and then paste this text to a power automate desktop

Text.SplitText.SplitWithDelimiter Text: PowershellOutput CustomDelimiter: $'''\\n''' IsRegEx: True Result=> TextList

You should get something like this

Get the values using the index position, so %TextList[1]% will give you the string calculated by $month_after.

If you wanted to return everything as a single string then you can write your last line something like

Write-Host "$($now_date), $($month_after) ...etc"