Reasons to cancel your Copilot subscription and switch to Claude for Office tasks.

If you use Microsoft 365 apps and need AI assistance, Microsoft Copilot is an obvious choice. It's tightly integrated into Microsoft apps and into Windows itself if you're using a PC, and works quite well right out of the box. However, many people also use Claude, an option that's superior to anything Copilot offers.

Therefore, as soon as Anthropic released the official add-ins for Microsoft 365 applications, they downgraded their Microsoft 365 subscription to the Personal plan and switched to using Claude for Office tasks, and have been increasingly impressed with Claude and its Opus 4.8 version.

Set up Claude for Office applications

One paid plan and one add-in is enough for everything.

To begin, you need to meet a few requirements. First, Claude for Office is only available to paid users, meaning anyone using the Claude Pro , Max, Team, or Enterprise plan. The free plan will not work, so keep that in mind if you're comparing it to Copilot.

You also need a Microsoft 365 subscription with desktop versions of Word, Excel, and PowerPoint (2016 or later) on Windows or Mac. The add-in also works on the web versions of these applications, so even browser-only users are supported.

Find Claude for Microsoft 365 on the Microsoft Marketplace , click Get it now , and sign in with your Microsoft account. From the items page, use the Open in Word , Open in Excel , and Open in PowerPoint buttons to attach the add-in to each application.

Then, the Claude icon will appear on the toolbar. Click on it, log in with your Claude account once, grant any necessary permissions, and the sidebar is ready. There's also an add-in for Outlook, currently in beta, if you want Claude to appear in your inbox. But that's beyond the scope of this article.

Ask Claude to edit the Word file.

Skills that turn it into a professional editor.

People primarily use Word to write and edit their articles, and the built-in spell-checking and grammar-checking tools miss many grammatical and formatting errors. Copilot can also proofread and edit, but it doesn't have access to the same set of Skills that Claude has. Skills are reusable sets of instructions that teach Claude how to perform a particular task in the same way each time.

Claude for Word comes with a skill /copy-edit, so instead of writing a prompt, just type /copy-editand press Enter . It scans the document in seconds, identifies seven errors to correct and one typographical consistency issue, and then automatically applies the corrections to all 27 paragraphs. The edits are recorded as tracked changes, so nothing is missed without your knowledge.

Next, provide a more specific instruction: Examine each sentence in the introduction for problems with wording, awkward word choices, or incorrect conjunctions. It offers several suggestions for improving the introduction, each with a brief explanation.

Another use case for writers is fact-checking. Ask Claude to check the article for factual errors and outdated information. It performed several web searches, confirmed most statements were accurate, and correctly highlighted the statements that needed attention. Word's built-in editor would never have done that.

Claude can help you with your Excel spreadsheet.

Claude writes the formula, and Excel performs the calculation.

You might think that a language model would be a weakness when working with numbers, but Claude doesn't do the calculations itself. It writes the formulas, and Excel does the calculations, which completely avoids the typical mathematical problems of AI. This add-in handles many different tasks and, frankly, it's superior to anything you've ever seen in Excel, and it's very good at self-checking.

It can help you quickly understand the structure of other people's workbooks. Just point it to a legacy file, and it will read every tab, cell, and formula, then explain how the worksheets are connected in easy-to-understand language. Ask it for a specific formula, and it will analyze structures like INDEX/MATCH step by step. It also fixes common errors like REF, VALUE, and loop references while explaining what went wrong.

Its self-checking capabilities are even more impressive. Drag and drop the supplier's PDF statement into the sidebar, and Claude will analyze the row items into a spreadsheet, then compare the rows to the subtotals and tax values ​​in the PDF before declaring the job complete. Previously, when provided with erroneous data, Claude transformed the data into a usable spreadsheet, and this Excel add-in also has a habit of self-checking its work.

Claude also has a keen eye for slides.

The editing is based on a template, not a general overhaul.

Claude also works with PowerPoint, so if you're planning to create a presentation slide from your Excel data, the add-ins can share context. With both applications open, you can ask Claude to create a summary slide for management from the Excel analysis it just completed, and it will automatically retrieve the figures without copy-pasting.

What sets Claude apart from typical AI slide builders is its template recognition. Claude reads the slide master, layout, fonts, and color palette before editing anything, so the new slides will fit the presentation perfectly instead of looking forced. It can generate a complete presentation from a single prompt, and the structure it chooses is logical rather than being added unnecessarily.

It's equally useful on existing presentations. Some people have used it to condense a six-bullet-point summary slide into three clear key points, merge two overlapping slides into one, and convert bullet points into original, editable charts. When asked to improve a boring set of slides, it will first ask if you want light, medium, or heavy edits and request approval before applying the changes.

Claude add-ins for Microsoft Office have some peculiarities. For example, the permission prompts, while logical, make it slower than Copilot's instant suggestions; conversations aren't saved after closing the file, and you have to pay for the Claude package in addition to your Microsoft 365 plan. Copilot is also still better integrated into Windows itself, and everything Claude creates still requires human review before release.

But if your work in these applications involves writing, editing, and occasionally using spreadsheets, then Claude is simply better than you at all three. And things will only get better in the future.