Microsoft Copilot Conversation History: Retention and Controls

Consumer Microsoft Copilot keeps the last 18 months of signed-in conversation history and shows it in the conversation list. Microsoft 365 Copilot follows separate organisational controls. This page maps the specific guides for finding, searching, exporting, recovering, organising, and deleting Copilot chats.

The complete Microsoft Copilot history guide

Which Copilot are you using?

"Microsoft Copilot" is a brand name applied to several distinct products, and each one handles conversation history differently:

• Copilot on the web (copilot.microsoft.com) — the standalone product, formerly Bing Chat. Saves history when you're signed into a Microsoft account. Most of the guides above assume this version.
• Copilot in the Edge sidebar — built into the browser, accessed via the sidebar icon or Alt+/. History persistence here is more limited than the web version.
• Microsoft 365 Copilot — the paid enterprise version inside Word, Excel, Teams, and Outlook. Governed by your organisation's Microsoft 365 data retention policy, not a personal setting.
• Copilot in Windows — the system-level assistant in the taskbar. The least persistent history of the four.

If you're not sure which one you've been using, it's almost always the web version if you access Copilot through a browser tab at copilot.microsoft.com rather than inside another Microsoft app.

How retention and deletion actually work

Microsoft documents an 18-month retention window for consumer Copilot conversation history. Product version still matters: Microsoft 365 Copilot follows organisational and compliance controls, and unsigned consumer sessions are not associated with a persistent account history. The limits and retention guide covers the distinctions.

Deletion is one-way. There's no "recently deleted" folder to restore from inside Copilot itself. If a conversation is gone, your realistic options are a browser cache from moments ago, a prior export, or a local index you'd set up in advance — covered in the recovery guide.

Separately, a conversation that seems to have vanished is often just failing to load rather than actually deleted — that's a more common, more fixable problem, and the not-loading guide walks through the fixes before you assume the worst.

The gap across all of these

None of the built-in tools solve the same problem: Copilot's own history view is a scrollable list with no keyword search, no cross-session search, and no export of the full archive at once — only individual conversations, one at a time. That's true whether your history is intact, thin on retention, or partially missing.

LLMnesia is a free Chrome extension that closes that gap without changing how you use Copilot. It indexes your Copilot web conversations locally, on your own device, as you use them, and makes them instantly searchable by keyword — alongside ChatGPT, Claude, Gemini, and the other platforms it supports. Nothing is uploaded, so there's no account to lose access to and nothing depends on Microsoft's own retention window.