OneDrive for Business file limits

Occasional Contributor

Can someone give me the definitive answer on ODfB file limits? Is there a 20,000 file limit as far as sync is concerned, as far as total storage (even with a 1TB total space limit), or are those numbers obsolete?

20 Replies

The definitive answer is here:


And here for the *old* ODFB client you should not be using anymore:

With the new sync client Microsoft has removed such limits so in theory you can sync on your PC / Mac as many items as you want

I'm getting different answers every time I ask the question. Some say that there are no limits (beyond the 1TB limit per ODfB account), and some talk about the 20,000 file limit.

@Vasil Michev

The second link you posted is about Groove, not about SPO with the NGSC!

Please edit your post, or there is the risk to add to confusion... :)


Whoops, that's what happens when you dont pay enough attention. Thanks @Salvatore Biscari :)

There appears to be 2 issues here with the number of files. 


1. If there is a great number of files that OD4B needs to keep in sync (no number known, haven't seen any limit published by Microsoft) then OD4B will attempt to keep those files in sync with the pc, regardless of whether or not Files On-Demand is enabled.  It would appear that OD4B runs on something like a timer job and goes through each and every file in the repository synced looking for changes.  This of course keeps files that have actually changed from syncing in a timely manner.  End users who are working with files and relying on them to sync in OneDrive for sharing will often not have good results and cause incidents to be created for help desk complaining that OD4B is not functioning.


2. When you initially turn sync on for a large SharePoint document library that may have 100's of thousands of files in it, OD4B has to look at each individual file and initial sync can take a very long time.  While this is occurring, syncing of any new or changed content is not happening.


There must be a better way to manage the files that OD4B has been tasked to sync.  Instead of 'touching' each file to see if it needs to be synced or initially synced, wouldn't it be better to simply pass a list of files to the client on demand (by folder per se)?  Then an event model that just looks for files that are in need of syncing and touching only those files, using the same list mechanism, possibly using JSON? 


What is Microsoft's response to any of these issues.  This is their tech community, but I don't see any Microsoft credentialed individual responding to any of these inquiries.  What say you, Microsoft?

@David Shumate 


You hit the nail on the head for the issues we have been experiencing. We probably have upwards of 400,000 files. Though not every user is syncing all of them, but at least around 100,000. We have 1GBs bandwidth and the majority of our PC's are newer with SSD's (we have found that we have less sync issues on SSD's then traditional HDD's) 


Do you know if the issue is the amount of files the user is syncing to their desktop, so unchecking unnecessary folders under "Choose Folders" in the settings would improve the syncing issues. Or is it just the amount of files in the that are in the sharepoint library, whether or not they are synced?

@Nathee021 It's been a month since I requested Microsoft to comment on my findings and nothing has been posted here, no one has reached out to contact me otherwise.


Per your questions, I wouldn't know any of the limits to which you inquire since there is nothing Microsoft has documented with regards to file limitation other than the GB configured for a OD4B account.


If they don't support large numbers of folders/files or syncing large GB's worth of files, then they should state that when you attempt to use the sync capabilities of OD4B.  Otherwise, it's supported.  That's how I see it.

@Nathee021 - the limit is currently 300K files syncing.  If you have more than that, MSFT warns OneDrive sync client will perpetually be looking at files for status change and therefore perpetual loop.  I have one user with 1.5M files, but we only sync about 250K and it works fine (so sync folder selection helps w/ issue).

@Lou Mickley 


Hey -thanks for your comment,


I had a couple questions:


1 - is this 300,000 per document library - or - in TOTAL that can be synced?

2- Do you know if that would affect "Files-on-Demand"  i.e. A user Syncing 3 or 4 document libraries with over 150,000 in each (total 450,000) but all in "File-On-Demand" so not actually syncing.

Kind regards

#1 - 300K TOTAL across all sources #2 - FonD does not impact this total Issue is not the time to sync the files, the issue is the time it takes to look through all the sources to see if sync of any files needed. As a result, as you get over 300K, you may see perpetual spinning sync icon.

@Lou Mickley I wonder why they do a "search and destroy" method to find the files that need updating instead of a simple event model, like we use everywhere else?

but when you have millions of files OD stays in a loop and never gives you the list of folders to pick

@Lou Mickley 


I have experimented, and If the Library has over 300k records than it is very slow.  So, if you have a single file library with 1 million records, and you try to only sync 250k of those records, it seems OneDrive still loops through all 1 million records at initial sync.  This causes huge performance issues.

Does anyone know if this new OneDrive will break us out of the 300000 file limitation for SharePoint sync?

I guess Microsoft is leaving this question unanswered for now. I could not find any documentation about it.
It's best to follow the OneDrive guru

I guess I feel the urge to test it out... I am going to spin up a test VM and I am going to create some files :) and keep a eye on the .dat file

@Rudy_Ooms_MVP Thanks for that info Rudy.


I guess we all have to be OneDrive guru's these days since Microsoft refuses to address the core issues associated with their client.  Those issues impose severe limitation upon our teams to conduct business properly; which is the sole purpose for Microsoft 365 app ecosystem after all.


1. 300000 files or greater in a document library can and often does lock up the OneDrive client from being able to continue to perform any synchronization of files with that document library or any other, no matter the size.

2. The sync buttons on document libraries that contain larger than 300000 files exist; no effort at all is made to restrict end users from getting into trouble and locking up their OneDrive client.

3. A OneDrive client that is locked up may appear to be functioning perfectly; when in reality it is not syncing anything any longer due to being locked up by a large syncing document library.

4. Absolutely zero documentation exists from Microsoft that points to any of these issues, only in passing can you find some documentation associated with these things and it is usually from the users, not the owners.


As I regularly am asked to migrate large file shares into document libraries as part of a migration path, it is critical to our operations that we understand these limits and deal with them accordingly.  If this new client is able to handle greater than 300000 files without the risk of locking up, it would be a game changer towards how we are able to integrate file share migrations in our tenant.  I figured asking the question in a Microsoft forum would be a good avenue to get that information.  Please let us know Microsoft, this is extremely important.