The short version: Copilot Studio caps every agent at 500 knowledge sources across all types, as at 23 September 2026. An uploaded file tops out at 512 MB, with 500 files allowed per agent. A fully integrated SharePoint source is capped at 25 site URLs under generative orchestration, four under classic. Dataverse allows two sources with 15 tables each under classic orchestration, unlimited under generative.
What Microsoft actually caps
Every number below comes from Microsoft's own quotas page and its knowledge sources summary, both current as at 23 September 2026.
| Limit | Value | Source |
|---|---|---|
| Knowledge sources per agent | 500 across all types | Copilot Studio quotas and limits |
| Uploaded file size | 512 MB per file | Copilot Studio quotas and limits |
| Uploaded files per agent | 500 files | Copilot Studio quotas and limits |
| SharePoint site URLs per agent | 25 (generative), 4 per node (classic) | Copilot Studio quotas and limits |
| Dataverse knowledge sources | 2 sources, 15 tables each (classic); unlimited (generative) | Knowledge sources summary |
| Public website search sources | 25 sites (generative), 4 (classic) | Knowledge sources summary |
The 500-source ceiling is enforced at publish time: add a 501st source of any type and the agent refuses to publish until something's removed.
Supported file types, and what won't upload
Files uploaded directly as a knowledge source support a wide range of formats: Word (doc, docx), Excel (xls, xlsx), PowerPoint (ppt, pptx), PDF, plain text (txt, md, log), HTML, CSV, XML, OpenDocument (odt, ods, odp), EPUB, RTF, Apple iWork (pages, key, numbers), JSON, YAML and LaTeX. Image, video, executable and audio files can't be used as uploaded documents on their own; an image only counts as knowledge when it's embedded inside a PDF with descriptive alt-text attached.
Uploaded files are stored in Dataverse, so the practical ceiling for a given environment is whichever comes first: the 500-file, 512 MB-per-file limit Copilot Studio enforces, or the Dataverse file storage allocation the environment has left. A firm running a near-empty Dataverse for Teams environment hits the storage wall before the file-count wall.
What it means for a firm under 20 staff
A firm under 20 staff building its first agent will not get near 500 knowledge sources; most internal agents run on a handful. The limit that actually bites is narrower and easier to trip: pointing an agent at more than 25 separate SharePoint sites, or more than four under classic orchestration, because someone added one URL per department instead of scoping the source to a shared library. Scoping a SharePoint knowledge source to a library rather than a whole site keeps you well under either ceiling and keeps the agent's blast radius smaller at the same time.
The other practical trap is a single oversized file: a combined policy manual exported as one 600 MB PDF fails outright, while the same content split into a handful of files under 512 MB each uploads cleanly.
The workaround when you need more
Switch from classic to generative orchestration first. It quadruples or removes several of the tighter classic caps: SharePoint goes from four URLs per generative-answers node to 25 for the whole agent, Dataverse goes from two sources to unlimited, and public website search goes from four sites to 25. Files already uploaded to the agent don't count against the 25-source generative search limit at all.
If the content genuinely needs to span more than 25 SharePoint sites, consolidate: point the knowledge source at a shared library or hub site that already aggregates the content, rather than adding every source site individually. For structured data outgrowing file uploads, moving it into Dataverse tables removes the file-count and file-size ceilings entirely under generative orchestration. Raising these caps doesn't change what an agent costs to run per question, which is worked through in Copilot Studio capacity: what 25,000 messages buys.
Common questions
How many knowledge sources can one Copilot Studio agent have?
500 across all types combined, as at 23 September 2026. Within that ceiling, a public website search source is capped at 25 sites under generative orchestration or four under classic orchestration, and the fully integrated SharePoint source is capped at 25 site URLs under generative orchestration or four per generative-answers node under classic orchestration.
What's the maximum file size for an uploaded knowledge source?
512 MB per file, with a ceiling of 500 uploaded files per agent. A larger file linked through SharePoint can still be found by a Microsoft Graph search, but generative answers only process SharePoint files up to 200 MB with a Microsoft 365 Copilot licence in the same tenant, or up to 7 MB without one.
Can Dataverse tables be used as a knowledge source?
Yes. Up to two Dataverse knowledge sources per agent with up to 15 tables each under classic orchestration; generative orchestration removes that cap entirely. Tables need to be standard or activity tables, and the maker needs read permission on each one.
Not sure which knowledge source fits your data?
Free 30-minute call. Tell me what you're grounding the agent on and I'll tell you whether it fits inside these limits.