How to Migrate File Shares to SharePoint (Bulk CSV with SPMT)

Say you’re moving two department shares, a 6-file Policies folder and a 4-file Marketing share, into one SharePoint library. Put both in a CSV file and let the SharePoint Migration Tool run them together.

In this tutorial, we’ll migrate file shares to SharePoint in bulk: plan the move, build the CSV (or JSON) file, run it in SPMT, check what landed where, and see when Migration Manager fits better.

The sample file shares we’ll use

Both shares go to the Migration Demo library on /sites/SPGuides. If you still need a target, first create a document library in SharePoint Online. See the SharePoint tutorials hub too.

Source share	Contents	Target folder
SPGuides Policies	HR (3 files), Finance (2 files), Company Holidays 2026.docx = 6 files	Migration Demo/Policies
Marketing Share	Campaigns (3 files), Brand Assets (1 file) = 4 files	Migration Demo/Marketing

For one folder, the SPMT wizard is enough: Single file share source, pick the folder, site and library, then Start. My post How to Use the SharePoint Migration Tool (SPMT) Step by Step covers every screen.

Plan the file share move first

Before you write the CSV, plan these:

• Inventory: list each share, its owner, size and target library.
• Clean up: delete duplicates and old junk.
• Restructure: flatten deep trees. See this SharePoint folder structure that scales helps here.
• Permissions: set up site groups first, following SharePoint permissions best practices.

Then check the limits that trip up old file servers:

Limit	What Microsoft documents
Path length	The full decoded path, including the file name, can’t exceed 400 characters
Invalid characters	" * : < > ? / \ |, plus leading or trailing spaces
Blocked names	.lock, CON, PRN, AUX, NUL, COM0-COM9, LPT0-LPT9, desktop.ini, _vti_, names starting with ~$
File size	250 GB per file

Pro Tip: Turn on Replace invalid filename characters in SPMT settings. With it off, those files are skipped, and a package with more than 100 errors gets blocked.

Method 1: Bulk migration with a CSV file (Recommended)

Use this for more than one share. Each row is one task, with no header row. Here’s the file I ran:

C:\Shares\SPGuides Policies,,,https://yourtenant.sharepoint.com/sites/SPGuides,Migration Demo,Policies
C:\Shares\Marketing Share,,,https://yourtenant.sharepoint.com/sites/SPGuides,Migration Demo,Marketing

How does this work?

#	Column	For a file share
1	Source	Required: the folder path
2	Source DocLib	Leave empty
3	Source SubFolder	Leave empty
4	Target Web	Required: the site URL
5	Target DocLib	Required: the library name, here Migration Demo
6	Target SubFolder	Optional: empty means the library root

That’s why three commas follow the path. Microsoft Learn’s format page actually lists 8 columns (the last two are hub site columns for SharePoint site migrations) and says all columns must be present. My 6-column file worked in SPMT 4.3.130.12, but to match the documented format, add two empty trailing commas:

C:\Shares\SPGuides Policies,,,https://yourtenant.sharepoint.com/sites/SPGuides,Migration Demo,Policies,,

Now run it. In SPMT, select File share > Add new migration and choose Bulk migration using JSON or CSV file.

Enter the CSV path in File path.

Review migration lists one row per task:

Select Next, then Start. Both tasks ran in parallel.

After about 1 minute, the Migration complete dialog showed 10 out of 10 items and 296.20 KB out of 296.20 KB.

Per task, Policies moved 6 of 6 items (183.99 KB) and Marketing 4 of 4 (112.21 KB).

So here’s the catch: with a target subfolder, the source folder’s contents land in it. I got Policies/HR, not Policies/SPGuides Policies/HR.

Method 2: Use a JSON file instead

JSON suits task lists built by a script. Here’s the first task in Microsoft’s format:

{
  "Tasks": [
    {
      "SourcePath": "C:\\Shares\\SPGuides Policies",
      "TargetPath": "https://yourtenant.sharepoint.com/sites/SPGuides",
      "TargetList": "Migration Demo",
      "TargetListRelativePath": "Policies"
    }
  ]
}

How does this work?

Only SourcePath and TargetPath are required; TargetListRelativePath is the subfolder.

Check the results

File share > View migrations showed both as Completed.

View reports opens a WF_ folder with Log and Report subfolders. Compare file counts in the library and check site permissions in SharePoint Online. To reorganize later, move folders in SharePoint Online.

Which method should you use?

Situation	Use
One folder, one-time move	SPMT single file share source
A few shares from one PC or server	SPMT bulk CSV
Task list built by a script	SPMT bulk JSON
Many file servers, large volume, central tracking	Migration Manager

Migration Manager lives in the SharePoint admin center and sends tasks to agents on several servers. It needs SharePoint admin rights and SMB 2.0+ sources. Moving home drives? Read the difference between SharePoint and OneDrive first.

Things to Keep in Mind

• CSV picked as a folder: a CSV path under Single file share source shows the error below. Choose the bulk option instead.
• Header row: don’t add one; every line is a task.
• Throttling: run big batches on evenings or weekends.
• Library design: follow these document library best practices.

Once the files are in SharePoint, these guides help you organize and secure them:

• SharePoint Document Set vs Folder: Which One Should You Use?
• SharePoint Contribute vs Edit Permissions: Key Differences and Best Uses
• Get SharePoint Folder Permissions Using PnP PowerShell
• How to Upload Files to a SharePoint Document Library Using PnP PowerShell

Frequently Asked Questions