# Microsoft breaks Excel's 40-year single-value cell rule New feature allows multiple values per cell, reshaping spreadsheet workflows - **Source:** [www.theregister.com - Articles](https://brifing.si/source/2c34ea50-d341-4a10-925d-12c012a9ad10) - **Published:** 2026-09-25 - **Topic:** [Data & AI](https://brifing.si/c/data-ai) - **Original article:** - **On Brifing:** https://brifing.si/s/abad2e84-07e1-4362-926e-d3ef204bf5e3 ## End of an Excel era Microsoft has fundamentally changed Excel's core architecture by allowing multiple values in single cells, breaking a 40-year convention. This shift enables new data structures like lists, arrays, and nested arrays within individual cells. The change is currently opt-in and available only in beta versions for Windows and Mac. Senior Product Manager Jake Armstrong positioned this as addressing modern collaborative workflows where multiple owners work on projects. ## Solving legacy limitations Traditionally, users had to cram multiple values into single cells as text strings or use helper columns. The new approach maintains data relationships while enabling individual item manipulation. Project owners can now be stored together yet remain available for filtering and calculations. This eliminates common workarounds that made spreadsheets harder to maintain and audit, though the feature isn't yet recommended for production workbooks. ## Technical implementation challenges The change requires updates to software libraries that interact with Excel files, as they expect single-value returns. Libraries like openpyxl, pandas, and calamine will need modifications to handle the new data types. Microsoft hasn't yet revealed how these structures will appear in .xlsx XML files. This impacts data import/export workflows across platforms including CSV, Google Sheets, and LibreOffice. ## Backward compatibility risks Early adopters report potential issues with existing features like PivotTables that weren't designed for multi-value cells. Users may need to flatten data structures temporarily until Microsoft updates dependent functionality. Some commenters warn the change could obscure business logic and complicate auditing processes that relied on Excel's predictable single-value model. ## New analytical possibilities Arrays in cells enable more complex data representations without external references. Nested arrays could simplify financial models and scientific calculations that currently require multiple sheets. The feature aligns Excel with modern database concepts where single fields often contain structured data. However, Microsoft cautions this remains a preview with undisclosed limitations. ## Collaboration workflow impacts The update reflects how Excel usage has evolved from individual analysis to team-based work. Multiple owners can now be properly associated with projects without text parsing. This change may reduce version control conflicts in shared workbooks by decreasing the need for auxiliary columns that different users might modify independently. ## Industry adoption timeline Microsoft hasn't announced when the feature will reach general availability. The beta period allows developers to update integrations and users to test compatibility. Organizations with complex Excel-based systems should monitor the rollout, as widespread adoption depends on third-party tool updates. The transition may mirror Excel's shift to ribbon UI in terms of user adaptation time. ## Future of spreadsheet design This change signals Microsoft's commitment to modernizing Excel beyond its original single-user paradigm. By embracing complex data structures, Excel positions itself against specialized analytics tools. The success will depend on how well the implementation balances power with Excel's signature accessibility. This could be the most significant structural change since pivot tables were introduced in 1993. ## Sources covering this story - https://www.theregister.com/applications/2026/09/25/microsoft-cells-out-crams-multiple-values-into-excel-boxes/5299294 — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._