Comparison · Microsoft 365 Copilot
Microsoft 365 Copilot vs Tessa: help inside each app, or one assistant for everything
Microsoft 365 Copilot brings AI into Word, Excel, PowerPoint, Outlook and Teams. Tessa is an assistant that works across your tools and takes on the work that falls between them: tasks, replies and follow-ups.
AI helps you write, but nobody keeps track
Having AI inside every app is convenient: summarise an Outlook thread, draft a Word document, get a recap of a Teams meeting. But you are usually the one who has to ask, and the one who has to remember what is still pending.
In a small company the problem is often different. What matters arrives by email, Slack and in meetings, and nobody turns it into tasks or follows it up. If you are looking for a Copilot alternative, it helps to separate an AI that helps when you call it from an assistant that works on her own.
How it works with Tessa
- 1
Connect whatever each person uses
Tessa works with Google Workspace and Slack, and with Microsoft 365 (Outlook, OneDrive and Teams) in beta. Each person connects their account in one click.
- 2
Review your first inbox
Tessa reads the last few days and shows what is waiting for a reply or action, prioritised and with the reply ready to send.
- 3
Write your first routine
For example: “every Monday, remind clients with overdue invoices”. Tessa understands it and runs it, asking for approval for anything that goes out.
- 4
Decide whether she sits alongside Copilot
You do not have to choose: keep Copilot inside your documents and let Tessa handle the follow-through.
What you get
- Works without being askedShe reads what comes in, creates prioritised tasks and drafts replies before you even open your inbox.
- Email, Slack and meetings togetherIf your team uses Slack as well as email, Tessa treats it as another source, with mentions and @Tessa in channels.
- Routines in plain languageWrite what you want to happen the way you would say it. No flows to configure, no technical skills.
- Built for small businessesTemplates by industry, the Spanish tax calendar and, in beta, invoices with Holded and bank reconciliation.
- Approval for anything going outEmails to clients, quotes or CRM notes wait for your go-ahead unless you say otherwise.
What Microsoft 365 Copilot is
Microsoft 365 Copilot is Microsoft’s AI assistant built into the Microsoft 365 apps, including Word, Excel, PowerPoint, Outlook and Teams. It can draft and summarise documents, help with spreadsheets, recap Teams meetings and answer questions using your organisation’s work data inside the Microsoft ecosystem.
Its big advantage is being where you already work if your company runs on Microsoft 365, with the management, security and compliance you already have set up there.
Information about Microsoft 365 Copilot is based on its public website as of October 2026; it may change.
How Tessa is different
Copilot is mainly help inside each app. Tessa is an assistant that works continuously across all of them: she reads what comes in, decides what matters, creates tasks, drafts replies and follows up, without you opening a particular app and asking.
She is also not tied to one vendor. Tessa is built on Google Workspace and Slack and works with Microsoft 365 in beta, which suits companies that mix tools, as most small companies and startups do.
- An inbox of tasks from email, Slack and, in beta, WhatsApp Business.
- Meeting notes with tasks per owner (Meet; Teams and Zoom in beta).
- Sales without a CRM, a company wiki and onboarding for new hires.
- Data stored in the EU and no individual metrics for managers.
When to choose Microsoft 365 Copilot
If your company runs entirely on Microsoft 365 and you want AI inside Word, Excel, PowerPoint and Teams to write, analyse and summarise faster, Copilot is the natural choice. It is built into the tools you already use and into Microsoft’s admin.
It is also the better option if you need help with spreadsheets or slide decks, which are not Tessa’s territory.
When to choose Tessa
Tessa is the better fit if your problem is not drafting but things slipping: unanswered emails, meeting commitments nobody remembers, deals going cold. Especially if you work with Google Workspace and Slack, or a mix of tools.
If your company is on Microsoft 365, note that the Outlook, OneDrive and Teams connection is in beta: it works, but has not yet been tested with as many real accounts as Google.
| Microsoft 365 Copilot | Tessa | |
|---|---|---|
| Main focus | AI inside the Microsoft 365 apps | An assistant working across your tools |
| Ecosystem | Microsoft 365 | Google Workspace and Slack; Microsoft 365 in beta |
| Help with documents, sheets and slides | ✓ Its strength | Context-aware documents in your Drive |
| Tasks from email without asking | Check its website | ✓ |
| Slack as a source of work | Not its focus | ✓ |
| Automatic follow-ups | Check its website | ✓ |
| Data stored in the EU (Tessa) | Check its data policy | ✓ |
What Tessa reads for each person stays private, your data is stored in the EU and nothing goes out without your approval.
Frequently asked questions
Is there a Copilot alternative for small businesses?
It depends on the job. For AI inside Word or Excel, Copilot is hard to replace on Microsoft 365. For an assistant that runs your email, Slack and meetings and does the follow-ups, Tessa is built for that.
Does Tessa work with Outlook and Teams?
Yes, in beta. Tessa connects to Outlook, OneDrive and Teams, but that connection has not yet been tested with as many real accounts as Google Workspace.
Can I use Copilot and Tessa together?
Yes. They complement each other: Copilot helps inside each document, and Tessa handles the tasks, replies and follow-ups that fall between apps.
Does Tessa work with Slack?
Yes. Slack is one of her main sources: she turns requests into tasks, and you can type “@Tessa create a task for Ana” or “summarise this thread” right in the channel.
Where does Tessa store data?
On EU servers, encrypted. What Tessa reads for each person is visible only to that person.
Can my team mix Google and Microsoft accounts?
Yes. Each person connects what they use: some can work with Gmail and Google Calendar, others with Outlook and OneDrive (in beta). Tessa treats everyone the same in the inbox, tasks and follow-ups.
Keep reading
- IntegrationsBetaAn AI assistant for Outlook and Microsoft 365Connect Microsoft 365 Outlook in one click. Tessa sorts your email into tasks, drafts replies that stay in the thread and books meetings on Teams.
- IntegrationsBetaAI notes for Microsoft Teams meetings: minutes and tasks, doneTessa joins your Teams meetings, writes minutes with decisions and tasks per owner, and sends the recap. No extra Microsoft licences required.
- FeaturesEvery email that asks for something becomes a taskTessa reads your email and Slack, turns every request into a prioritized task with a due date and clears what's already done. Try it free.
- FeaturesAutomations you write the way you'd say themWrite “every Monday, remind clients with overdue invoices” and Tessa does it every week, with your approval for anything leaving the company.
- CompareGemini in Google Workspace vs Tessa: which one your company needsGemini helps inside Gmail, Docs and Meet. Tessa works on her own across Google and Slack: tasks, replies and follow-ups. See how the two fit together.
- CompareChatGPT for business vs Tessa: a chat for everything, or an assistant who works on her ownChatGPT for business is a general-purpose assistant. Tessa works on her own across your email, Slack and meetings and follows up. Compare and try free.
What does your team look like?
Same AI for both. Where you start is what changes.
- Best fit for this page
Companies
30 to 250 people
What gets decided gets done
Minutes and tasks from every meeting, commitments that get followed up and a pulse per team, without watching anyone.
Startups
5 to 30 people
Grow without losing the thread
Tasks from email and Slack, follow-ups, sales and investors, without everything landing on the founders.
Connect your email and Slack and let Tessa get your day ready.
Start freeFree plan for teams of up to 3 people. Anything that leaves the company waits for your approval.