Copilot in Outlook: Does It Reply to Emails for You? What It Does, What It Costs, and What It Will Not Do

What Copilot in Outlook actually does (verified feature list)

Microsoft's Copilot in Outlook hub lists seven features: Chat with Copilot, Draft an email message, Make email drafts sound like you, Summarize an email thread, Prioritize my inbox, Email coaching, and Create a meeting and agenda (support.microsoft.com, retrieved 23 September 2026). Here is what each does according to Microsoft's own article for it.

Draft with Copilot. In a new message, reply or forward, select the Copilot icon, choose Draft, type a prompt and select Generate; adjust tone and length, then "Keep it". The article's final step is the one that matters here: "Edit the draft as needed, and then select Send." It applies to Outlook for Microsoft 365, Outlook for Mac, new Outlook for Windows, and Outlook for Android and iOS ("Help me write" and "Help me reply" on mobile), and it does not support plain-text messages (support.microsoft.com, retrieved 23 September 2026).

Coaching by Copilot. You write the email, then ask Copilot to review it for "tone, clarity, and reader sentiment", with an "Apply all suggestions" button. Same client list as Draft; on Mac it is "only available in the latest version of Outlook for Mac. Legacy Outlook isn't supported" (support.microsoft.com, retrieved 23 September 2026).

Summary by Copilot. A summary at the top of a long thread with numbered citations that jump to the source email, plus a "Summarize a file" option in new Outlook for PDF, PowerPoint or Word attachments. Microsoft lists classic and new Outlook for Windows, the web, Mac and mobile (support.microsoft.com, retrieved 23 September 2026).

Prioritize my inbox. The closest Copilot gets to inbox automation. It assigns a priority to incoming mail "based on factors like senders, job titles, and content", shows an up arrow with a short explanation, and lets you teach it rules such as "It's about a customer complaint". It only prioritises mail received after you switch it on and skips subfolders and encrypted messages. It labels; it does not reply (support.microsoft.com, retrieved 23 September 2026).

Chat with Copilot in Outlook. A side-pane chat split by licence: without the add-on you can "ask questions about your inbox, calendar, meetings and other limited data and take action directly in Outlook"; with it you can "interact with your inbox, calendar, meetings, chats, and enterprise data". A related article covers natural-language triage commands (pin, flag, archive, delete, move), English only (support.microsoft.com, retrieved 23 September 2026).

Schedule with Copilot. From a thread, Copilot proposes a meeting title, agenda and attendees for you to review before sending. Listed for new Outlook for Windows, and "only available if you have a Microsoft Copilot (Work) license" (support.microsoft.com, retrieved 23 September 2026).

One scope limit from Microsoft's Copilot in Outlook FAQ applies across all of these: "Copilot scenarios in Outlook are only available on a user's primary mailbox. They are not available on a user's archive mailbox, group mailboxes, or shared and delegate mailboxes" (support.microsoft.com, retrieved 23 September 2026).

What it costs and which licences include it (verified table)

Pricing is where most third-party write-ups go wrong. The figures below are from microsoft.com and learn.microsoft.com, retrieved 23 September 2026, in US dollars as Microsoft publishes them. Microsoft changes these often; treat this as a snapshot.

Sources: microsoft.com/microsoft-365-copilot/pricing and /pricing/individuals; learn.microsoft.com Copilot licensing and overview pages; all retrieved 23 September 2026.

Three details worth knowing. The add-on is exactly that: Microsoft lists Business Basic, Standard, Premium, Apps for Business and Teams Essentials as prerequisites, so you cannot buy Copilot for Outlook alone, and Microsoft 365 E7 is the only plan listed as including it outright (learn.microsoft.com, retrieved 23 September 2026). Copilot Pro no longer appears on Microsoft's individual pricing page: Copilot in Outlook now comes inside Microsoft 365 Personal, Family, Premium and Pro, and Family members cannot share it. Consumer usage is metered in AI credits; asking Copilot to "summarize my inbox" deducts one credit (support.microsoft.com, retrieved 23 September 2026).

Does Copilot reply to emails automatically?

No. Every feature in Microsoft's Copilot in Outlook documentation is invoked by you, on a message you have open, and ends with you deciding what to do. The Draft article's last step is "Edit the draft as needed, and then select Send." The FAQ adds that "it's important that you review, edit, and verify anything it creates for you" (support.microsoft.com, retrieved 23 September 2026).

That is deliberate, and for personal email it is right: nothing happens to a message until someone opens it and asks, and there is no setting that turns Draft with Copilot into "reply to everything that arrives". One nuance for completeness: Microsoft's admin docs describe a usage-billed Copilot Cowork feature that "carries out tasks across your Microsoft 365 environment on your behalf" for Premium-licensed users (learn.microsoft.com, retrieved 23 September 2026). We found no Microsoft page describing it answering inbound email unattended, so we make no claim either way; every Outlook-specific feature Microsoft documents is on demand.

If what you need is a message that goes out while you are away, Outlook's built-in automatic replies do that (see our Outlook auto-reply guide). If you need real answers to real questions sent while nobody is at the desk, that is a different category, covered below.

Copilot's three gaps for a customer inbox

None of these are flaws. They are the boundaries of an in-client assistant, and they only matter if your inbox is where customers write to you.

1. It does not read the inbox for you. Copilot acts on the message you have open. Prioritize my inbox labels new mail, but it does not classify a message the way a support team needs (refund request, booking enquiry, complaint) and it does not route or answer it. Chat can summarise your emails about a customer, but only once you ask. Between your asks, the inbox is exactly as unattended as before.

2. It knows Microsoft 365, not your policies and prices. This needs nuance, because the grounding is genuinely good. With the paid add-on, responses are grounded "in organizational data (emails, files, meetings, calendars, teams, or organizational relationships) through Microsoft Graph"; without it, Copilot Chat "can't use organizational data via Microsoft Graph" and you upload the file yourself (learn.microsoft.com, retrieved 23 September 2026). So a licensed user can point Copilot at the refund policy in SharePoint and get a draft from it. What Copilot does not have is a curated, business-owned body of approved answers that every reply must stay inside, with a rule that says "if it is not in here, do not guess". For a customer asking whether your cancellation window is 14 or 30 days, that is the whole problem.

3. It never sends. A draft nobody reviews is an email nobody answered. If sixty customer emails arrive on a Saturday, Copilot helps you write sixty good replies on Monday; the customers still waited two days. And because Copilot is unavailable on shared and delegate mailboxes (support.microsoft.com, retrieved 23 September 2026), the sales@ or support@ inbox where those emails land is the one place it cannot be used at all.

When Copilot is the right tool

Often. If you already pay for Microsoft 365 and your day is mostly email to colleagues, clients and partners, Copilot is the obvious choice; no third-party tool will match its access to your calendar, Teams chats and SharePoint files. It is the right tool when:

• The bottleneck is your own writing speed. Draft and Coaching are built for exactly that, and on many business plans the basic tier is already included.
• The email is internal or one-to-one. Catching up on a 40-message project thread, or turning it into a meeting, is where the Microsoft Graph grounding earns its price.
• You want a human on every send. Some businesses and some regulators require it. Copilot's model guarantees it.
• It is a personal inbox. On Microsoft 365 Personal or Family, Copilot in Outlook is included for the subscription owner.

For a wider look at the drafting-assistant category, including tools that plug into Outlook without a Copilot licence, see our best AI email assistants for small business roundup and our InReply vs Fyxer comparison.

When you need an email agent instead

The category difference is simple: an assistant helps you write and is triggered by you; an agent answers and is triggered by the email arriving. You need an agent when:

• It is a shared customer inbox. Copilot is primary-mailbox only, so on a shared address the assistant model cannot even be switched on. See our guide to the Outlook shared mailbox.
• The same questions arrive every day. Opening hours, pricing, availability, how to cancel. Drafting each answer faster is still drafting each answer.
• Emails arrive when nobody is working. Evenings, weekends, bank holidays. On-demand tools are idle when there is no one to demand.
• The answer must come from approved material. Policy, price and procedure questions where the reply has to match the document, not the model's best guess.

InReply is built as that second kind of tool, for Outlook and Microsoft 365 as well as Gmail. It connects to the mailbox you already have through Microsoft OAuth (no new client, no migration, revoke it any time), classifies each inbound email, and writes a reply grounded only in the knowledge your business uploads (FAQs, PDFs, CSVs, documents or a linked website), organised into playbooks with their own knowledge, tone and constraints. Ghost Mode saves every reply as a draft in Outlook, on every plan. Autopilot, per playbook, sends replies itself with human-like delays, business-hours awareness and a confidence threshold below which nothing goes out. Anything it cannot answer is raised to a human as a draft or a tracked, assignable action item in the team workspace. Full detail on the AI email assistant for Outlook page and in how the AI email agent works.

InReply plans are Starter at £39/month (500 emails, 1 inbox, 2 users), Growth at £79/month (2,000 emails, 3 inboxes, 5 users) and Scale at £149/month (5,000 emails, 5 inboxes, 10 users), with a custom Business tier above. Every plan starts with a 14-day free trial and no credit card. See full pricing. To be equally plain about limits: InReply has no scheduling, no calendar, no thread summaries and no Teams integration. If those are the jobs, Copilot is the tool.

Using Copilot and InReply together on the same Outlook mailbox

They work at different layers, so they coexist without conflict. Copilot lives inside the Outlook client and acts on what you have open; InReply works at the mailbox level through Microsoft Graph and acts on what arrives, whether or not Outlook is open. A setup that works well:

1. Connect the customer-facing mailbox to InReply and upload the knowledge that answers your repeat questions. Start in Ghost Mode, so every reply appears as a draft in Outlook.
2. Open the drafts as normal. If one needs a softer or firmer tone, run Coaching by Copilot on it before sending.
3. Switch on Autopilot playbook by playbook once the drafts have earned your trust, opening hours and pricing first, and keep Copilot for your own correspondence.

Neither tool changes the other's licensing: InReply does not need a Copilot licence.

Bottom line

Copilot in Outlook is a good assistant, and for personal and internal email on a Microsoft 365 plan it is probably the best one you can get, because it is already there and often already paid for. Everything it does is something you ask for on a message you have open. It does not watch the inbox, it does not answer from your approved knowledge unless you point it at the file, it cannot be used on a shared mailbox, and it never sends. If your problem is your own email, use Copilot. If your problem is customers waiting for answers, you need an agent.