🔒 Zero Query Logging (ZQL)¶
⚠️ Internal insight — do not share publicly. Much of this content comes from internal field guidance, Supportability wiki, and internal NDA decks. Use for personal learning and customer conversations only. A public blog version will be created separately using only publicly verifiable sources.
Last updated: April 2026 | Status: Limited GA (April 2026) | GA target: FY26 Q4 (Apr–Jun 2026)
What is Zero Query Logging?¶
Zero Query Logging (ZQL) is a privacy feature for web grounding in Microsoft 365 Copilot and Copilot Chat that prevents Copilot-generated web search queries from being logged or retained by Bing.
The Problem It Solves¶
When Copilot needs up-to-date information (market trends, recent policies, public statistics), it:
- Generates a web search query based on the user's prompt
- Sends that query to Bing
- Uses the results to ground the response
Many regulated customers have disabled web search entirely because they don't want any data artefacts created outside the Microsoft 365 compliance boundary. This means their Copilot is missing:
- ❌ Latest information grounding
- ❌ External knowledge synthesis
- ❌ Up-to-date reasoning
ZQL fixes this — customers can safely enable web grounding without Bing retaining any query data.
Simple Analogy¶
🏨 Think of it like a hotel concierge (Copilot) who calls a travel agency (Bing) to get flight info for a guest. Normally, the travel agency logs the call. With ZQL, the concierge uses a private hotline — the travel agency answers the question but never records who called or what was asked.
How It Actually Works¶
┌──────────────────────────────────────────────────────────┐
│ WITHOUT ZQL │
│ │
│ User Prompt → Copilot → Bing (full index) │
│ ↓ │
│ Query logged in Bing ❌ │
│ Results → Copilot → Response │
└──────────────────────────────────────────────────────────┘
┌──────────────────────────────────────────────────────────┐
│ WITH ZQL │
│ │
│ User Prompt → Copilot → Curated Index (subset of Bing) │
│ ↓ │
│ NO query logged ✅ │
│ Results → Copilot → Response │
└──────────────────────────────────────────────────────────┘
The Key Architectural Change¶
Microsoft created a separate, curated search index for web queries through Copilot:
- Contains a subset of the full Bing index with the most popular answer types
- Once ZQL is enabled, Copilot only uses this curated index for web grounding
- Bing does not log query data or identifiers from this curated index
This is what makes "zero logging" technically possible — it's not just a flag on Bing, it's a different search pipeline entirely.
What ZQL Protects (and What It Doesn't)¶
| Data Type | Without ZQL | With ZQL |
|---|---|---|
| Web queries stored in Bing logs | ⚠️ Yes | ✅ Eliminated |
| Prompt-derived identifiers logged externally | ⚠️ Yes | ✅ Eliminated |
| Data artefacts outside M365 compliance boundary | ⚠️ Created | ✅ Reduced |
| Purview Audit Log (prompts, responses, search keywords) | ✅ Logged | ✅ Still logged |
| eDiscovery access | ✅ Available | ✅ Still available |
| Enterprise Data Protection | ✅ Applied | ✅ Still applied |
🧠 The Key Nuance¶
ZQL stops Bing from logging queries. It does NOT stop Purview from logging them.
- External retention → removed
- Internal compliance logging → preserved
This is a huge governance win — customers get privacy externally while keeping compliance internally.
The Trade-Off: Privacy vs Breadth¶
Because ZQL uses a curated subset of the Bing index (not the full index), there's a trade-off:
| Aspect | Full Bing Index | ZQL Curated Index |
|---|---|---|
| Web coverage | 🌐 Full internet | 📦 Most popular answer types |
| Query logging | ⚠️ Logged in Bing | ✅ Zero logging |
| Freshness | Real-time | Near real-time (curated) |
| Compliance risk | Higher | Lower |
For most enterprise queries (market data, policy info, product comparisons), the curated index is sufficient. Niche or very recent topics might have slightly less coverage.
How to Enable ZQL¶
Prerequisites¶
- Microsoft 365 Copilot licence
- Office Apps Admin or Global Admin role
- Access to Cloud Policy Service for Microsoft 365
Step-by-Step¶
- Sign in to Microsoft 365 Apps admin center
- Navigate to Customization → Policy Management
- Create or edit a policy configuration
- Find the policy: "Enable Zero Query Logging for Copilot web searches"
- Set to Enabled
- Assign to tenant or specific user group (for testing)
- Save and wait 24 hours for propagation
⚠️ Recommended Activation Order¶
Microsoft recommends enabling ZQL before enabling web search:
- First: Enable "Enable Zero Query Logging for Copilot web searches" policy
- Wait 24 hours for full propagation
- Then: Enable "Allow web search in Copilot" policy
This ensures ZQL is active before any web queries start flowing.
What Users See¶
- Nothing! There is no user-facing indicator that ZQL is enabled
- Web grounding works exactly the same from the user's perspective
- The change is entirely backend — queries just aren't logged by Bing
Which Customers Need This?¶
High Priority (proactively raise ZQL)¶
| Industry | Why ZQL Matters |
|---|---|
| 🏛️ Government | Data sovereignty, no external data artefacts |
| 🛡️ Defence / DIB | Security classification requirements |
| 🏦 Financial services | Regulatory compliance, audit requirements |
| 🏥 Healthcare | Patient data sensitivity, HIPAA considerations |
| 🎓 Education / Research | Research data protection, student privacy |
| ⚖️ Legal | Client privilege, confidentiality obligations |
The Conversation Opener¶
Many of these customers have already disabled web search in Copilot due to privacy concerns. ZQL is the answer that lets them turn it back on:
"I see you've disabled web search in Copilot — was that because of data retention concerns with Bing? There's a new feature called Zero Query Logging that eliminates that risk while keeping web grounding active."
Customer Talk Track¶
Simple Version¶
"By default, Copilot may generate web search queries to get up-to-date information. With Zero Query Logging, Microsoft ensures those Copilot-generated web queries are never retained by Bing. That means you can safely enable web grounding while keeping all prompt and query data inside the Microsoft 365 compliance boundary and governed through Purview."
For Security/Compliance Teams¶
"ZQL provides a separate, curated search pipeline that doesn't create data artefacts outside your M365 boundary. Your prompts, responses, and search keywords are still logged in Purview for eDiscovery and compliance — but Bing never sees or stores them. It's the best of both worlds: web-grounded answers with enterprise-grade privacy."
For CISOs¶
"ZQL addresses the #1 blocker we hear from security teams: 'We turned off web search because we don't want query data leaving our compliance boundary.' With ZQL, you can re-enable web grounding with zero external retention risk. Internal logging through Purview remains fully intact for your compliance obligations."
Comparison: Web Search Options¶
| Configuration | Web Grounding | Bing Query Logging | Purview Logging | Best For |
|---|---|---|---|---|
| Web search OFF | ❌ No | N/A | ✅ Yes | Maximum isolation (but Copilot less useful) |
| Web search ON, ZQL OFF | ✅ Full Bing index | ⚠️ Yes | ✅ Yes | Unrestricted use, less regulated industries |
| Web search ON, ZQL ON | ✅ Curated index | ✅ No | ✅ Yes | Recommended for regulated industries |
Timeline & Availability¶
| Milestone | Date |
|---|---|
| Private Preview | FY26 Q3 (Jan–Mar 2026) |
| Limited GA | ~7 April 2026 |
| Full GA target | FY26 Q4 (Apr–Jun 2026) |
⚠️ Internal insight: ZQL is not enabled by default. As of April 2026, customers may need to request access before the policy appears in Cloud Policy Service. Check with your account team if the policy isn't visible.
Related Controls & Features¶
ZQL is part of a broader set of Copilot privacy controls:
| Control | What It Does | Relationship to ZQL |
|---|---|---|
| Web search toggle (admin) | Enable/disable web grounding entirely | ZQL is meaningless if web search is off |
| Purview DLP for Copilot | Block sensitive data in web search prompts | Complements ZQL — prevents sensitive data from reaching any search |
| Enterprise Data Protection | Keeps all Copilot data within M365 boundary | ZQL strengthens this by removing Bing logging |
| UX transparency (2025) | Users see exact queries Copilot sends to Bing | Builds trust alongside ZQL |
| Sensitivity Labels | Prevent Copilot from processing labelled content | Separate control — applies to Graph data, not web queries |
| Restricted Content Discovery | Block specific SharePoint sites from Copilot | Controls internal grounding, ZQL controls external grounding |
FAQ¶
Q1: Does ZQL affect Copilot's quality?¶
Slightly. The curated index covers the most popular answer types but is a subset of the full Bing index. For most enterprise queries, the difference is negligible. Very niche or breaking-news queries might have less coverage.
Q2: Can I enable ZQL for some users and not others?¶
Yes. The Cloud Policy can be applied at tenant level or scoped to specific user groups. Useful for piloting before full rollout.
Q3: How do I know ZQL is working?¶
There's no user-facing indicator. You can verify by checking that the policy is active in Cloud Policy Service. Purview Audit Logs will still show web search keywords (proving Copilot is using web grounding), but Bing won't have corresponding logs.
Q4: Does ZQL apply to agents and Copilot Studio?¶
ZQL applies to Microsoft 365 Copilot, Copilot Chat, and the Researcher agent. For custom Copilot Studio agents that use web search, check the specific agent configuration.
Q5: What about the EU Data Boundary?¶
ZQL complements EU Data Boundary by reducing external data artefacts. However, the curated search index location should be confirmed with your Microsoft account team for specific data residency requirements.
Q6: Can Purview DLP and ZQL work together?¶
Yes — and they should. DLP prevents sensitive data from being sent in web queries. ZQL prevents those queries from being logged. Together, they provide defence-in-depth for web grounding privacy.
Sources¶
- Zero Query Logging Overview — Microsoft Learn
- Data, privacy, and security for web search — Microsoft Learn
- Web query transparency — Tech Community
⚠️ Internal sources (Supportability wiki, Field FAQ, NDA decks) informed this page but are not linked publicly.
📝 Future: Create a public blog post on aguidetocloud.com using only publicly verifiable sources when ZQL reaches full GA.