When you switch from Classic Outlook to the new Outlook for Windows, search results often appear in a different order than you expect. Classic Outlook returns results in the order they appear in the folder — newest first — while the new Outlook uses a relevance ranking algorithm that prioritizes items it thinks are most important. This article explains why the ranking difference occurs, how to adjust search settings to get closer to the classic behavior, and what limitations remain in the new Outlook.
Key Takeaways: Controlling Search Ranking in New Outlook
- Settings > General > Search > Relevance: Toggle the Relevance toggle off to disable smart ranking and show results by date.
- Ctrl + E shortcut: Opens search in both Classic and New Outlook so you can test ranking differences immediately.
- Search filter bar > Sort dropdown: Manually re-sort results by Date, From, or Subject after a search completes.
Why New Outlook Changes Search Result Order
Classic Outlook displays search results in the default sort order of the current folder, usually by received date with newest items on top. The new Outlook uses a relevance-based ranking engine that evaluates sender, subject keywords, attachment presence, and message recency to determine which results appear first. This engine is designed to surface the most relevant item at the top of the list, even if it is not the newest email in the folder.
The technical root cause is that the new Outlook runs on a different search infrastructure. Classic Outlook uses the Windows Desktop Search index and the local Outlook data file. The new Outlook uses the Microsoft Search service, which is the same engine used in SharePoint, OneDrive, and Microsoft 365. This cloud-based search service applies a machine learning model to rank results. When you search for a term like “invoice,” the new Outlook may show an email from a frequent contact before a newer email from an unknown sender.
The ranking algorithm considers these factors in order of weight:
- Exact match in the subject line
- Recent messages from the same sender
- Messages with attachments
- Messages you have replied to or forwarded
- Messages in your primary inbox versus clutter or junk
Because Classic Outlook does not use any of these ranking signals, users switching to the new Outlook often feel that the order is random or broken. The fix is not to change the algorithm — you cannot do that — but to adjust the search experience settings to reduce the effect of relevance ranking.
Steps to Turn Off Relevance Ranking in New Outlook
- Open Settings in New Outlook
Click the gear icon in the top-right corner of the window. Select View all Outlook settings at the bottom of the Settings pane. - Navigate to Search settings
In the Settings window, select General on the left, then click Search. - Toggle off Relevance
Under the Search section, find the toggle labeled Relevance. Click the toggle to set it to Off. The toggle turns gray when disabled. - Close Settings and test
Close the Settings window. Press Ctrl + E to open the search box. Type a search term and observe the results. Results now appear sorted by date with the newest items first.
After disabling relevance, the new Outlook still uses the Microsoft Search index, but the ranking order changes to a simple date descending sort. This behavior is closer to Classic Outlook but not identical because the search still operates on the cloud index rather than the local PST file.
Alternative Method: Sort Results Manually
If you prefer to keep relevance ranking on for some searches but need exact order for a specific query, you can manually re-sort the results after the search completes.
- Run a search
Press Ctrl + E and type your search term. Wait for the results to appear. - Open the Sort dropdown
Above the search results list, locate the column header row. Click the Sort dropdown button, which shows the current sort criterion. - Select Date
Choose Date from the dropdown. The results re-sort immediately with the newest messages at the top.
Manual sorting applies only to the current search session. The next search reverts to the default ranking behavior unless you also turned off the Relevance toggle.
If Search Still Shows Unexpected Order After Fix
Search results still show relevance ranking even after I turned off the toggle
The Relevance toggle in new Outlook is a client-side setting that tells the UI to sort by date instead of relevance score. However, the underlying search index still returns results in relevance order by default. The client re-sorts them after receiving the full result set. If you have a very large result set — more than 200 items — the client may not re-sort all results, leaving some relevance-ranked items at the bottom of the first page. To see all results sorted correctly, reduce the search scope. Use the search filter bar to limit results to a specific folder or date range before searching.
The search box does not show a Relevance toggle at all
The new Outlook for Windows is still rolling out in stages. Some accounts, especially those in organizations with specific Microsoft 365 update channels, may not have the Relevance toggle in Settings. If you cannot see the toggle, you cannot disable relevance ranking through the UI. The only workaround is to use the manual sort method after each search. Microsoft plans to add the toggle to all accounts by the end of 2025.
Classic Outlook search order changes after installing the new Outlook
Installing the new Outlook does not alter Classic Outlook search behavior. Classic Outlook continues to use the Windows Search index and its own PST-based search. If Classic Outlook search order changes after you install the new Outlook, the cause is likely a Windows Search index rebuild triggered by the installation. Rebuild the Windows Search index by going to Control Panel > Indexing Options > Advanced > Rebuild. This restores the classic search order.
| Item | Classic Outlook Search | New Outlook Search |
|---|---|---|
| Search engine | Windows Desktop Search (local PST index) | Microsoft Search (cloud index) |
| Default sort order | Date descending (newest first) | Relevance score descending |
| Customization | Sort column header click | Settings toggle + Sort dropdown |
| Ranking factors | None (folder sort order) | Subject match, sender frequency, attachments, recency |
| Works offline | Yes (local PST) | Limited (cached cloud data) |
Disabling the Relevance toggle in new Outlook settings brings the search order closer to the Classic Outlook experience. You can also use the manual Sort dropdown after each search to reorder results by date. The underlying search engine remains different, so exact parity with Classic Outlook is not possible in the new Outlook. If you need precise folder-order searching, consider keeping Classic Outlook as your primary client until the new Outlook adds more sorting options.