Managed MetaData and Document Libraris

Hi akelly,

Great question — this is a very common requirement in SharePoint Online.

In the modern experience, there’s currently no supported way to display a modal or popup when users drag & drop files into a document library in order to force metadata entry.

That said, when required metadata columns are configured on a library, SharePoint does enforce completion in a different way:

👉 If a document is uploaded without all required fields completed, it remains incomplete (and checked out if versioning/check‑out is enabled). In that state, the file is only visible to the author and site administrators until the metadata is filled in.

👉 If your goal is to enforce metadata usage, here are a few approaches, ordered from the most out‑of‑the‑box to the most custom:

• Default column values (per folder or library): helps prefill metadata; users can adjust values if needed.
• Document Sets: useful when documents belong to a structured container with shared metadata.

➡️ The following options typically rely on an intake experience rather than allowing users to upload files directly into the library:

• SharePoint Library Forms (internal users only, external accounts not supported yet): allows file upload through a form that can require metadata before submission.
• Microsoft Forms + Power Automate: common pattern to collect files and metadata, then route them into SharePoint.
• Power Apps custom forms: replaces the default file properties form and allows richer validation and UX.
• Custom development solutions: for example SPFx, a dedicated upload portal, or third‑party solutions.

Hopefully this gives you a clearer picture of what’s possible today and which option best fits your scenario.

Best regards