How to Save List as a Template using PowerShell in SharePoint?

Requirement: Save SharePoint list as a template using PowerShell

How to Save List as template in SharePoint?
List templates in SharePoint provides great re-usability without having to recreate every single columns. Say for e.g. you may have created a custom list (say: Projects) in a SharePoint site collection  with all relevant columns, Now you might want this list structure in other site collections, without recreating the list on every single site. To save a list or library as template:

• Go to your SharePoint list >> Navigate to list settings by going to List tab on the ribbon and then List Settings.
• Click on "Save list as Template" under Permissions and Management group.
• Provide the name for template File and Template name
• Choose the appropriate option for "include content" and Click OK.
  

You will see "Operation Successful" page and your template will be uploaded to "List Template Gallery".

Generally, it's a good idea to create list templates at top-level site, so that any site underneath can utilize the template!

PowerShell Script to save list as a template:
Here is how to save list as template in SharePoint 2013 using PowerShell.

#Add SharePoint Snapin
Add-PSSnapin Microsoft.SharePoint.PowerShell -ErrorAction SilentlyContinue 

#Configuration parameters
$WebURL="https://projects.crescent.com"
$ListName="Parent Projects"
$TemplateName="Parent Project Template"
$TemplateFileName="ParentProjectTemplate"
$TemplateDescription="Crescent Inc. Parent Project List Template"
$SaveData = $true

#Get the Web and List objects
$Web = Get-SPWeb $WebURL
$List = $Web.Lists[$ListName]

#Save List as Template
$List.SaveAsTemplate($TemplateFileName, $TemplateName, $TemplateDescription, $SaveData)
Write-Host "List Saved as Template!"

Now, You can create a new list instance from the template saved: Create List from List Template in SharePoint using PowerShell

If you need to save a SharePoint Online List as template, use: SharePoint Online: PowerShell to Save List as Template