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Connect Gemini to your email
Add your own mailbox to Gemini as a custom MCP connector: paste its URL, sign in, pick the mailbox. Outlook, Gmail, Yahoo or IMAP, walked live.
Add Mailbox MCP to Gemini as a custom connector
To connect Gemini to your email, you add Mailbox MCP as a custom connected app: you give Gemini one URL, sign in to us once, and Gemini can read, search and, if you allow it, draft and send in that mailbox. These are the screens Gemini showed on , in an account we've had connected since 2 November.
You need the mailbox connected in the control panel first, because that's where the mail server sign-in is checked and kept. Gemini never sees it.
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Open Customize, then Connectors
In Gemini on the web, open Customize in the sidebar and choose the Connectors tab (its address is gemini.google.com/
customize/ connectors). Gemini's Settings, bottom left, then Connected Apps opens the same page. 
Connectors in Gemini, 14 November 2026. + Custom is top right. -
Select + Custom and paste the MCP server URL
+ Custom opens "Connect to an MCP server", the form for a Gemini MCP connector. It asks for one thing: the MCP Server URL. Paste the mailbox's own URL there. Gemini only takes an address that starts with https://, and ours does.
MCP Server URL One per mailbox, from its Connector tabhttps://mcp.mailbox-mcp.com/db/mcp/YOUR-MAILBOX-KEYUnder Additional settings, Show more reveals a Client ID and a Client secret. Leave both empty. Gemini registers itself with our server, so there's nothing to copy across. Then select Next.
Connect to an MCP server, with our example URL typed in. Client ID and secret stay empty. The note at the foot is Google's: by adding the link, you're allowing Gemini to send information to an app Google hasn't reviewed. That's true of every custom app, and it's why the next screen is ours, asking what Gemini may do.
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Choose the mailbox and what Gemini may do
Gemini opens our sign-in in a pop-up, headed "Connect a mailbox?". The mailbox from your URL is already chosen. Pick Read only, Draft and file or Send and delete, then select Connect this mailbox. Start low if you're unsure: you can raise it later without touching Gemini.
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Check it's connected
The pop-up closes and your Gemini custom connector is listed under Custom apps, at the foot of the Connectors page, with the Mailbox MCP logo beside it. Ours showed the mailbox's address as its name. Its ... menu offers Use now, Disconnect and Delete.
Under Custom apps, with our logo. The menu holds Use now, Disconnect and Delete.
The sign-in says Google, not Gemini
Our sign-in shows the name an app registers with, and Gemini registers
as Google. The return address it shows is on
oauth-redirect.
Use the Gemini email connector in a chat
In a chat, type @ in the prompt box. Gemini's own hint says it: "Type @ for connectors, skills and more". A list opens with your connectors under Connectors, the custom app among them. Pick it, then ask your question.
Picking it is how you make sure Gemini uses your mailbox for that prompt, and Google's help page says the same: enter @ and select the custom app. Ask for something only your mailbox can answer, and name the mailbox if you've added more than one.
Try this first
List my 5 most recent emails with sender and subject, and tell me which need a reply from me. Don't change anything.
Pick your mailbox with @ first. Asking changes nothing: listing and reading never set the read flag, so your unread markers stay exactly as they were.
What we saw connecting Gemini to email
We first connected Gemini to one of our own business mailboxes on 2 November 2026, from a personal Google account in the UK on the Google AI Pro plan. We connected it again on 11 November, and we've read mail through it since.
- Gemini registered itself with our server, so there was no client ID or secret to find.
- It stayed connected. Between 2 and 11 November that first connection renewed its access with our server 27 times, and it was never revoked.
- Gemini showed our logo on the custom app, because our server publishes its icons for apps to use.
- Reading through Mailbox MCP left every message as it was. Nothing is marked read unless you ask.
It's early days for Gemini and MCP, on Google's side and on ours. We've read mail through it, but we haven't recorded a send from Gemini yet, so this page doesn't claim one. We'll add what we see.
Try it on your own mailbox: 5 MCP calls a day are free, with no card, and Pro raises a mailbox to 1,000 a day. Either is enough to connect Gemini and see it answer.
Who can add a custom MCP connector to Gemini
Google sets the rules for custom apps on its help page, and they're narrower than you might expect. To add one, it says you must:
Be 18 or over and in the US. Sign in to the Gemini app with a personal Google Account. Have Keep Activity on.
Google, Connect & manage custom apps for Gemini Apps
Read that against what we saw and two things stand out. Our account is in the UK, not the US, and + Custom was there and works. We can only say the country rule didn't stop us. The other two look firm: a work or school account isn't a personal one, and Keep Activity is a setting Google asks you to leave on.
So if your Connectors page has no + Custom button, check those 3 things first. Google also says custom apps work in English only for now, and that you add them in the Gemini web app. Once added, Google says they work in the Gemini mobile app too.
Connect Gemini to Outlook or Microsoft 365
Gemini reaches an Outlook mailbox through Mailbox MCP like any other: the mailbox connects to us, then to Gemini as a custom app. Through us it can read, search, reply inside the thread, file and read attachments, at the level you choose.
A work mailbox connects with one Microsoft sign-in: connect Outlook for work (Microsoft 365). A personal Outlook.com, Hotmail or Live address connects over IMAP after one switch in Outlook.com's settings: connect Outlook.com and Hotmail shows where it is.
Gemini and Gmail through Mailbox MCP
A Gmail or Google Workspace mailbox connects to Mailbox MCP with an app password, which needs 2-Step Verification by phone or authenticator app: connect Gmail walks through it. If Google says the setting isn't available, Gmail app password not available explains the usual cause.
Google has Gmail features of its own in Gemini. The free email connectors compared sets what Google documents beside what Mailbox MCP does, job by job, each with the day it was read.
Yahoo Mail and iCloud Mail in Gemini
Both connect to Gemini through Mailbox MCP. Yahoo Mail connects as an IMAP mailbox with a Yahoo app password, made under External connections on Yahoo's Account Security page: connect Yahoo Mail has the steps.
iCloud Mail needs an app-specific password from your Apple Account, and the same password opens your iCloud calendar: connect iCloud Mail and your Apple calendar.
Gemini and IMAP email on your own domain
Email on your own domain, from a web host, Fastmail, Zoho or GMX, reaches Gemini through Mailbox MCP over IMAP, with the same tools as any other mailbox. You add it in the control panel once, with the address and password your mail app already uses, and the panel looks up the server settings.
Connect any IMAP mailbox has the details. And because Mailbox MCP is a hosted, remote MCP server, there's nothing to install or keep running on your own computer for Gemini to reach it: remote and local MCP servers explains why that matters.
What Gemini may change in your mailbox
Two things stand between Gemini and a change to your mail. The first is Gemini's own. Google's help page puts it in one line:
Currently, Gemini requires manual confirmation for any write actions.
Google, Connect & manage custom apps for Gemini Apps
That's a good default, and note the word "currently": it's Gemini's setting, and Google can change it. A confirmation prompt is also only as good as the moment you read it, which is why the second thing is ours.
The level you chose in step 3 is enforced on our server, not by Gemini. Read only reads, searches and checks, and changes nothing. Draft and file adds drafts, filing and flags. Send and delete is everything the mailbox can do.
At the first two, there's no sending tool on the connection at all, and a call for one is refused here before Gemini is asked anything. Mailbox MCP security sets out both layers.
Change what Gemini may do, or disconnect it
Every connection shows on the mailbox's Connector tab in our control panel, under the name of the app that made it. Gemini's shows as Google, for the same reason the sign-in did, with its permission level and when it last signed in.
Change raises or lowers what Gemini may do, with no need to touch Gemini. Disconnect ends the connection at once. A connection can only ever reach the one mailbox it was approved for.
In Gemini, the custom app's ... menu has Disconnect and Delete. Google says Disconnect unlinks the server but keeps the app listed, so you can connect it again later, and removing the app unlinks it as well.
Disconnect in both places
Disconnecting in Gemini stops Gemini using the app. To be sure the door is shut on our side too, also press Disconnect beside Google on the mailbox's Connector tab in the control panel. That ends the grant itself.
For a second mailbox, add a second custom app with that mailbox's own URL. Each one opens one mailbox, the same rule as in every other app.
Questions about connecting Gemini to email
How do I connect Gemini to my email?
Add Mailbox MCP to Gemini as a custom connected app. On gemini.google.com, open Customize, then Connectors, and select + Custom. Paste the connector URL from that mailbox's Connector tab in our control panel into MCP Server URL, leave Client ID and Client secret empty, and select Next. Our sign-in opens in a pop-up: choose the mailbox and what Gemini may do with it, and you're done.
Can I connect Gemini to Outlook email?
Yes, through Mailbox MCP. A work or school Outlook mailbox on Microsoft 365 connects to us with one Microsoft sign-in, and a personal Outlook.com or Hotmail address connects over IMAP. Then you add that mailbox to Gemini as a custom connected app, the same way as any other. Gmail, Yahoo Mail, iCloud Mail and IMAP mailboxes on your own domain work the same way.
What is the Gemini MCP server URL for my mailbox?
The mailbox's own connector URL, from its Connector tab in our control panel. It starts with https://mcp.mailbox-mcp.com/ and ends with that mailbox's key, and Gemini asks for exactly that: a URL that starts with https://. Each mailbox has its own URL, so a second mailbox is a second custom app.
Why is + Custom missing from Gemini Connected Apps?
Google's help page lists who can add a custom app: you must "Be 18 or over and in the US", sign in with a personal Google Account rather than a work or school one, and have Keep Activity on. We've used it from a personal account in the UK, but if your account doesn't show + Custom, one of those requirements is the likely reason. Custom apps are added on the web, not in the phone app.
Why does the sign-in say Google instead of Gemini?
Because Gemini registers itself with our server under the name Google, and our consent screen shows the name an app gives itself. Its return address is on oauth-redirect.googleusercontent.com, which is Google's. So when you add the connector in Gemini and our sign-in says Google is asking to open a mailbox, you're on the right screen.
Can Gemini send emails through Mailbox MCP?
Only if you connect it at Send and delete, which is the level with the sending tools. Google says "Currently, Gemini requires manual confirmation for any write actions", so expect Gemini to ask you before it acts. We have read mail through Gemini since 2 November 2026, but we haven't recorded a send from it yet. Read only and Draft and file have no sending tool at all.
Can I connect Gemini to Yahoo Mail or iCloud Mail?
Yes, through Mailbox MCP. Yahoo Mail connects over IMAP with a Yahoo app password, and iCloud Mail with an app-specific password from your Apple Account. Once the mailbox is in our control panel, you add its connector URL to Gemini as a custom connected app, like any other mailbox.
Does Mailbox MCP keep a copy of my email?
No. Mailbox MCP reads your mail from the mailbox when Gemini asks and keeps no copy of your messages. Gemini never sees your mailbox password: it signs in to us, and we keep your mail server credential encrypted at rest with AES-256. Reading a message doesn't mark it read.
Where to go next
Once Gemini can reach the mailbox, what AI can do with your email has ideas for what to ask, and Mailbox MCP security says what we hold and what we never keep.
The same mailbox works in other assistants too, with the same URL: Claude.ai, ChatGPT and Grok each have their own page. Mailbox MCP pricing has the free allowance and Pro.
- Whether + Custom appears on the free Gemini plan. The account we used is on Google AI Pro, and Google's help page names no plan.
- Whether it appears for accounts outside the US and the UK. Google lists the US as a requirement; ours is a UK account and it works.
- Using the connector from the Gemini phone app. Google says a custom app added on the web works there too; every connection we made, and every chat we checked, was in a web browser.
- Work and school Google accounts. Google says a personal account is required, so we have not tried one.
Read 14 November 2026 Every value on this page came off Google: Connect & manage custom apps for Gemini Apps on that day. The steps and the screenshots are our own, from a personal Google account in the UK on the Google AI Pro plan, the same day. If it has changed since, tell us and we will read it again.