---
title: "Best AI email clients for 2026: 8 apps compared"
description: "Eight AI email clients compared on what their AI does, the mail they work with and the price in 2026, from Nextmail and Superhuman to Gmail and Outlook."
url: "https://nextmail.sh/blog/best-ai-email-client-2026"
---

[Blog](https://nextmail.sh/blog.md)[AI](https://nextmail.sh/blog/tags/ai.md)

# Best AI email clients for 2026: 8 apps compared

Eight AI email clients compared on what their AI does, the mail they work with and the price in 2026, from Nextmail and Superhuman to Gmail and Outlook.

Benjamin Nextmail team

October 31, 2026 8 min read

TL;DR

- Best overall: Nextmail, if you want an assistant that files, replies and runs tasks for you, on your own domain or your Gmail and Outlook, for one price per workspace. It is ours, so check the details below.
- Best for speed: Superhuman, the fastest client on Gmail and Outlook, at $30 a month per person, with Ask AI and auto drafts on the $40 Business plan.
- Try the free AI first: Gmail now drafts and summarises at no cost, and eligible Microsoft 365 plans include Copilot Chat.

Every email app has an AI button now. In January, Google brought Gmail into what it calls the Gemini era and made its writing help and thread summaries free for everyone. In June, Notion announced it would close Notion Mail in September, because its users would rather have AI agents handle their email than open an inbox.

The second piece of news matters more than the first. In 2026 the question is no longer which app writes the nicest draft. It is which one does the work while you are somewhere else, and how safely it lets an agent in.

A word on bias before the list: Nextmail is ours, and it sits first because we built it around exactly that question. What we say about every other app comes from its own pricing and help pages as of October 2026, all of them linked under References, so you can check our work. If you want the basics first, [What is an email client?](https://nextmail.sh/blog/what-is-an-email-client.md) explains how every one of these apps works underneath.

## How we compared them

- **What the AI does without you.** Summaries and drafts are table stakes now. We looked for an assistant that files, replies and runs tasks on its own, and asks before it sends.
- **Which mail it works with.** Some clients read only Gmail, some host the mail themselves, and a few do both.
- **Room for agents.** Whether Claude, ChatGPT or your own code can work in the mailbox, and whether you can limit what they reach.
- **The bill for a team.** A price per person grows with every hire, so we looked at a team of five as well as one person.

## The short list

| App | Best for | Works with | Price |
| --- | --- | --- | --- |
| Nextmail | AI that does the work | Your own domains, plus Gmail, Outlook, Yahoo and iCloud mailboxes | Free, then $20 a month for the whole workspace |
| Superhuman | Speed | Gmail and Outlook | $30 a month per person, $25 billed yearly |
| Shortwave | AI search on Gmail | Gmail | $30 a month per seat |
| Gmail with Gemini | Free AI in the inbox you have | Gmail | Free, with more on Google AI Pro |
| Outlook with Copilot | Companies on Microsoft 365 | Outlook and Microsoft 365 | Copilot Chat included, Copilot Business from $18 a user |
| Spark | A budget client on every platform | Most providers | Free, with +AI from $10 a month |
| Apple Mail | Free AI on Apple devices | The accounts already in Mail | Free with Apple Intelligence |
| Proton Mail | Privacy | Proton | Free, then $4.99 a month for Mail Plus |

## 1. Nextmail: best for AI that does the work

Nextmail is a mailbox and a client in one. You point a domain you own at it, and every address on that domain can receive mail, including the ones you never created. If your mail lives at Gmail, Outlook, Yahoo or iCloud, you can [connect that mailbox](https://nextmail.sh/docs/knowledge/addresses/connected-mailboxes.md) instead: it stays at the provider, and you work it from Nextmail.

The AI is built to act, not only to write. [Ask your inbox](https://nextmail.sh/docs/knowledge/ai/ask.md) is a chat that finds, files, labels, archives and replies, on every plan, Free included. [Tasks](https://nextmail.sh/docs/knowledge/ai/tasks.md) run plain instructions by themselves, on a schedule or when mail arrives: "every weekday at 8, tell me which conversations need a reply and draft one for each." You choose how much each task may do alone, down to asking before every change. Drafts follow your own writing style, long threads come with a summary, and suggested replies sit under the latest message.

Agents get the same mailbox. Claude Code, Codex, Cursor and ChatGPT connect over MCP with a browser sign-in, and you choose what each one may reach: one workspace, a set of permissions, all of your addresses or a few, and an end date. An agent you approved as read-only does not even see a tool that sends. The details are in [what an agent can reach](https://nextmail.sh/docs/mcp/scope.md).

**Price:** per workspace, not per person. Free covers one domain and 10 AI actions a day, and Starter is $20 a month for 50 domains and 50 actions a day. On a paid plan, adding a colleague never changes the bill. See [pricing](https://nextmail.sh/pricing.md).

**Watch out for:** the AI allowance is counted in daily actions (a draft, a rewrite, one turn of the assistant), with pay as you go past it, so heavy users should compare the plans. And getting the most from Nextmail means moving a domain's mail to it, which is a bigger step than installing a client on top of Gmail.

It runs on the web, [iPhone and Android](https://nextmail.sh/download.md), and any mail app can open the same addresses.

## 2. Superhuman: best for speed

Superhuman is still the fastest way through a busy inbox. Everything has a keyboard shortcut, and the Starter plan includes Superhuman AI to write messages, suggest instant replies and summarise threads. Business adds Ask AI, auto drafts, custom auto labels and an MCP server, in beta, that lets Claude or ChatGPT search, draft and send through your inbox.

**Price:** Starter is $30 a month per person, or $25 billed yearly. Business is $40, or $33 billed yearly. There is no free plan.

**Watch out for:** Superhuman is a client, not a mailbox. It works on top of a Gmail or Outlook account you still pay Google or Microsoft for, so a team of five on Business pays $200 a month for the client alone. Our [Superhuman comparison](https://nextmail.sh/compare/superhuman.md) runs the numbers.

## 3. Shortwave: best AI search on Gmail

Shortwave rebuilt the Gmail inbox around an assistant you can ask anything about your mail, and its plans are named by how much AI you get. Business, at $30 a seat a month, runs Claude Sonnet 4.6 with up to 50 threads per AI search and five years of AI search history. Premier, at $45, adds adaptive thinking and twice the usage, and Max, at $120, moves up to Claude Opus 4.6. It runs on the web, the desktop, iPhone and Android.

**Watch out for:** it is built on Gmail, so Outlook and Microsoft 365 accounts are out, and the seat is billed on top of the Google account underneath it.

## 4. Gmail with Gemini: best free option

If your mail is in Gmail, start here, because it costs nothing to try. Since January, everyone can use Help Me Write to draft or polish a message, Suggested Replies, and AI Overviews that summarise long conversations. Asking your inbox a question and Proofread need a Google AI Pro or Ultra subscription, and AI Inbox, a briefing of what needs you instead of a list of everything, was announced as a test for trusted users ahead of a wider release.

**Watch out for:** the features reached the US, in English, first. And Gemini helps you read and write faster, while the sorting and the answering are still yours.

## 5. Outlook with Copilot: best for Microsoft 365 companies

If your company already runs on Microsoft 365, Copilot is the path of least resistance. Copilot Chat comes with eligible Microsoft 365 plans at no extra cost, and the Microsoft 365 Copilot Business add-on brings Copilot into Outlook and the rest of Office, where it summarises threads and drafts replies.

**Price:** Copilot Business is $25.20 per user a month on monthly billing, or $18 a month on a yearly commitment, a first-year offer that runs from July 1 to December 31, 2026, against a normal $21. That is on top of the Microsoft 365 plan itself.

**Watch out for:** you pay per seat on top of per seat, so every hire adds two subscriptions to the bill.

## 6. Spark: best budget client on every platform

Spark, from Readdle, runs on iPhone, Mac, Windows and Android and puts most kinds of account in one inbox. Its +AI and AI Assistant come with the Plus plan, at $10 a month or $99 a year, and Pro, at $20 a month or $199 a year, adds Autopilot, auto drafts and unlimited AI meeting notes.

**Watch out for:** every paid plan meters +AI with a monthly allowance, +AI stays switched off until you turn it on, and the free plan gets only a short preview of it.

## 7. Apple Mail: best free option on Apple devices

On a recent iPhone, iPad or Mac, the Mail app already has AI built in. Apple Intelligence writes a short summary under each message in the inbox, summarises a whole conversation when you ask, and Priority Messages lifts time-sensitive mail to the top. It works with the accounts you already have in Mail, and it costs nothing.

**Watch out for:** Apple Intelligence is not available on every device, in every language or in every region, and it helps you read faster rather than doing the work for you.

## 8. Proton Mail: best for privacy

Proton Mail encrypts your mailbox so that Proton cannot read it, and its AI follows the same idea. Proton Scribe drafts and improves emails, and it can run on Proton's servers or download a model to your own device, so your words never leave it.

**Price:** Mail Plus is $4.99 a month, or $3.99 billed yearly. Scribe comes with the Duo, Family and Visionary plans, and it is a paid add-on on Proton for Business.

**Watch out for:** the AI only writes, it works only in the web app and the Mac app, and its on-device mode is English only. Search and integrations are narrower than elsewhere, which is the price of the encryption. Our [Proton comparison](https://nextmail.sh/compare/proton-mail.md) goes into it.

## How to choose

- **You are happy in Gmail and want help writing.** Turn on Gemini first. It is free, and it may be all you need.
- **Speed is the bottleneck.** Superhuman, if the price per person works for your team.
- **Your company lives in Microsoft 365.** Copilot, since Copilot Chat is already included.
- **Privacy comes before everything else.** Proton Mail.
- **You want the inbox handled, not just faster.** Choose an assistant that acts: one that files, replies and runs tasks on a schedule, asks before it sends, and lets your agents in on your terms. That is the reason we built Nextmail.

## Before you let an AI into your inbox

Whichever app you pick, check three things first. Can it send without asking you? Can you limit which addresses and actions it reaches, and take that back later? And where does the model run, on your device or on someone's servers? An assistant that answers all three clearly is one you can hand real mail to. If your agents need a mailbox of their own, our guide to [email as a mailbox](https://nextmail.sh/blog/email-as-a-mailbox.md) covers the options.

Nextmail is free to start, with the assistant on every plan. [Create a workspace](https://nextmail.sh/signup.md) and point it at a domain, or connect the mailbox you already have.

- [AI](https://nextmail.sh/blog/tags/ai.md)
- [Email clients](https://nextmail.sh/blog/tags/email-clients.md)
- [Comparisons](https://nextmail.sh/blog/tags/comparisons.md)

## References

1. 1 [Gmail is entering the Gemini era](https://blog.google/products-and-platforms/products/gmail/gmail-is-entering-the-gemini-era/) Google
2. 2 [Notion Mail is shutting down, but your Gmail inbox isn't going anywhere](https://www.androidauthority.com/notion-mail-is-shutting-down-3681674/) Android Authority
3. 3 [Choose your Superhuman Mail plan](https://superhuman.com/plans/mail) Superhuman
4. 4 [Superhuman Mail MCP Server](https://help.superhuman.com/hc/en-us/articles/49810745762067-Superhuman-Mail-MCP-Server) Superhuman
5. 5 [Shortwave pricing](https://www.shortwave.com/pricing/) Shortwave
6. 6 [Microsoft 365 Copilot pricing](https://www.microsoft.com/en-us/microsoft-365-copilot/pricing) Microsoft
7. 7 [Spark pricing](https://sparkmailapp.com/pricing) Readdle
8. 8 [Use Apple Intelligence in Mail on iPhone](https://support.apple.com/guide/iphone/iph9ae667055/ios) Apple
9. 9 [Proton Scribe writing assistant](https://proton.me/support/proton-scribe-writing-assistant) Proton
10. 10 [Proton Mail pricing](https://proton.me/mail/pricing) Proton

Keep reading

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## Your email, on your own domain.

Nextmail puts your domains, sending and inbox in one place, with the full API on every plan, the free one included.

[Open mail](https://nextmail.sh/mail/inbox) [Get Started](https://nextmail.sh/signup.md)[All articles](https://nextmail.sh/blog.md)