How to Write a String to a File in PowerShell

To write a string to a file in PowerShell, use Set-Content. It creates the file, or replaces whatever is in it. To add more text to the end, use Add-Content:

Set-Content -Path C:\psfaqs\notes.txt -Value 'Server patching starts at 9 PM.'
Add-Content -Path C:\psfaqs\notes.txt -Value 'Expect a 15-minute outage.'
Get-Content -Path C:\psfaqs\notes.txt

Output:

Server patching starts at 9 PM.
Expect a 15-minute outage.

Those two cmdlets cover most jobs. Below I’ll show how to write variables, multiple lines and arrays, how to append, and the encoding differences between PowerShell 7 and Windows PowerShell 5.1 that trip people up.

I tried all of this in PowerShell 7.6 and Windows PowerShell 5.1 on Windows 11. Where the two versions disagree, you’ll see both results.

Which command should you use?

Command	What it does	Good for
Set-Content	Writes text, replacing the file’s content	Most writes
Add-Content	Appends text to the end of the file	Logs and running lists
Out-File	Writes output the way the console shows it	Tables and command output
> and >>	Shortcuts for Out-File and Out-File -Append	Quick one-liners
[System.IO.File]::WriteAllText()	Writes a string in one .NET call	Exact control, no trailing newline

The practical difference is that Set-Content writes plain strings, while Out-File sends objects through the formatter first. More on that below.

Write a variable to a file

Put the variable inside double quotes and PowerShell expands it. Here I build an invoice line and format the total as dollars:

$customer = 'Contoso'
$total    = 1249.5
$line     = "Invoice for $customer, total {0:C}" -f $total

Set-Content -Path C:\psfaqs\order.txt -Value $line
Get-Content -Path C:\psfaqs\order.txt

Output:

Invoice for Contoso, total $1,249.50

Single quotes don’t expand variables, so you get the literal text instead:

$customer = 'Contoso'
Set-Content -Path C:\psfaqs\order.txt -Value 'Customer: $customer'
Get-Content -Path C:\psfaqs\order.txt

Output:

Customer: $customer

If you’re not sure which quotes to use, single vs double quotes in PowerShell covers the rules.

How do I write multiple lines to a file in PowerShell?

Pass an array. Set-Content writes each element on its own line:

$servers = 'WEB01', 'WEB02', 'SQL01'
Set-Content -Path C:\psfaqs\servers.txt -Value $servers
Get-Content -Path C:\psfaqs\servers.txt

Output:

WEB01
WEB02
SQL01

To keep everything on one line instead, join the array first:

$servers = 'WEB01', 'WEB02', 'SQL01'
Set-Content -Path C:\psfaqs\servers.txt -Value ($servers -join ', ')
Get-Content -Path C:\psfaqs\servers.txt

Output:

WEB01, WEB02, SQL01

Use a here-string for a block of text

For longer text, like a config file, a here-string is easier to read. Everything between @" and "@ is written as is:

$config = @"
Environment=Production
Region=East US
MaxUsers=250
"@

Set-Content -Path C:\psfaqs\config.txt -Value $config
Get-Content -Path C:\psfaqs\config.txt

Output:

Environment=Production
Region=East US
MaxUsers=250

Append text to a file

You have three ways to append: Add-Content, Out-File -Append and the >>