What is New in Excel for October 2025

Welcome to the October 2025 update. This month, look for Agent Mode in Excel (Frontier) in the Tools menu of Copilot for Excel. Additionally, PivotTable #SPILL and accessibility assistant updates are now available to Insider users on Windows and Mac. Formula by Example has also rolled out to the Current Channel for Excel on Windows.

Excel for web​

Agent Mode in Excel (Frontier)
Agent Mode in Excel lets you describe a task in natural language and then works with you to plan, reason, iterate, and validate the outcome.

An early preview of Agent mode is available via the Frontier program for Microsoft 365 Copilot licensed customers and Microsoft 365 Personal, Family, or Premium subscribers (under the Microsoft Services Agreement). Agent Mode works in Excel on the web and is coming soon to desktop. Learn more about it in our announcement blog.

To try it, look for Agent Mode in the Tools menu of Copilot in Excel.

Excel for Windows and Mac​

PivotTable #SPILL (Insiders)
PivotTable #SPILL! brings the familiar #SPILL! experience from dynamic arrays to PivotTables. If something is blocking your PivotTable from expanding – such as text, merged cells, tables, or the edge of your spreadsheet – you’ll see a #SPILL! error. This lets you address the issue at your own pace, so you can keep working without disruption and stay focused on your analysis. Read more here >



Accessibility Assistant updates (Insiders) #FIA
Recent changes reduce false positives, better reflect real accessibility needs, and help content authors prioritize addressing truly impactful issues. Read more here >

Excel for Windows​

Formula by Example
Formula by example looks for patterns as the user enters data in the worksheet. When it recognizes a pattern, formula by example offers a formula to fill the rest of the column with the recognized pattern. Read more here >

Formula by Example, previously available in Excel for the web, is now also available to Excel for Windows users on the Current Channel.