Microsoft 365 can be a confusing place when it comes to file storage. It offer you several places to put your files, but doesn't explain the difference between them. Predictably, everyone makes a different decision about where to storing things which inevitably results in three versions of the same document in three different places, with nobody sure which is current, and a fear of deleting any of them in case it was the good one.
It's fixable, and the rule is simpler than people expect.
OneDrive is yours. SharePoint and Teams belong to the business.
That's actually most of it. The question isn't which app you like, it's whether this document is your own work in progress, or something the business needs to be able to find without you.
OneDrive is personal storage. Your drafts, your notes, the spreadsheet you're still working out, the things nobody else needs yet.
You can share from it, and that works perfectly well for a one-off. But it's tied to your account, and that has a consequence people rarely think about until it bites: when someone leaves the business, their OneDrive goes with them. There's a grace period of 30 days once your account is removed that the contents of your OneDrive can be retrieved by someone else, but if the only copy of a live client document is in a departed colleague's OneDrive, that's now a job rather than a non-event.
Rule of thumb: if you'd be uncomfortable with this file disappearing when you do, it shouldn't live here.
Here's the thing that clears up most of the confusion: Teams files are SharePoint files.
When you upload a document to a Teams channel, it goes into that team's SharePoint site. Same file, same place and Teams is simply a friendlier door into it. You're not choosing between them, and you don't need to decide which is "the real one."
That means anything the business relies on belongs in a Teams channel or on a SharePoint site. It's owned by the team rather than a person, permissions follow the team, and when someone leaves nothing moves. The work stays where the work was.
There's one trap.
A file you drop into a Teams chat, for example a one-to-one message or a group chat, rather than a channel, doesn't go to SharePoint at all. It's uploaded to the sender's OneDrive.
So the document everyone's been referring to for months, the one that lives in the project group chat, is sitting in one person's personal storage, which is fine, right up until that person leaves.
Channel, not chat, for anything that matters.
It's also worth bearing in mind that a file saved to the desktop or a local Documents folder has no version history, no recycle bin anyone else can reach, and no copy anywhere if that laptop is lost or stolen. It's invisible. Nobody can find it, nobody knows it exists, and when the person who made it is on holiday it may as well not. So use those cloud storage options!
Every business hits a point where it has outgrown "everyone saves wherever." Usually the symptom isn't a crisis, it's the slow tax of duplicate documents, version confusion, and the awkward week after someone resigns when nobody can find what they were working on.
Agreeing this in a ten-minute conversation is far cheaper than untangling it two years later. And it's as simple as a decision, not a technical project: the tools are already there and already paid for.
If your files have grown organically and nobody's quite sure what's where any more, that's normal and it's very fixable. Get in touch and we'll help you work out a structure that suits how your business actually operates, rather than how Microsoft assumed it would.