AI Email Assistants in 2026: What Gmail and Outlook Already Include, and When a Paid Tool Is Worth It

Two things changed in this category and most guides have not caught up. The AI in Gmail and Outlook is now bundled into the Workspace and Microsoft 365 plans many people already pay for. And Superhuman, the premium client this category was built around, was acquired by Grammarly and repriced — its email plans now run $25 to $40 per member per month depending on tier and billing.

So the useful question is not which assistant writes the best email. It is what you already have, what a paid tool adds on top, and whether that tool actually acts on your inbox or just leaves drafts for you to send. This guide covers six tools in three groups on exactly that basis. Every figure is linked to the vendor’s own pricing page or documentation and reflects the published US price as of September 2026.

Three kinds of email AI

Built into your email platform. Gemini in Gmail and Copilot in Outlook. Nothing to install, nothing new to learn, and increasingly included in the subscription rather than sold separately.

A replacement email client. Superhuman and Shortwave replace Gmail or Outlook entirely with a faster interface built around keyboard shortcuts, AI drafting and split inboxes. You change where you read email.

A layer on your existing inbox. SaneBox and Fyxer sit on top of Gmail or Outlook without asking you to switch apps. They sort, triage and in some cases draft, but you keep your current client.

The third group is the easiest to trial and the easiest to abandon, because nothing about your setup changes if you stop paying.

What you may already have

Before paying anything, check your existing subscription.

Gemini in Gmail drafts replies, summarises long threads, and offers a “help me write” layer inside the standard Gmail interface. Google’s Workspace plan comparison lists “Gemini in Workspace apps” as included in the Business Standard, Business Plus and Enterprise SKUs, and as “Limited” on Business Starter, with a separate “AI Expanded Access” add-on sold separately for more. So for most Workspace customers above the entry tier, the drafting layer is already paid for.

Copilot in Outlook does the equivalent for Microsoft: drafting, thread summaries, and pulling context from across Microsoft 365. The important caveat is that Microsoft states plainly that “a qualifying Microsoft 365 subscription is required to purchase Copilot” — it is a per-user add-on rather than an inclusion, so what you have depends on which licence your organisation bought.

For most people writing a normal volume of email, that is enough. A $30 a month client is a hard sell next to an inbox you already pay for.

Does it draft, or does it send?

This is the question that matters most and the one almost no comparison asks. Autonomy levels differ sharply, and the vendors are not equally clear about it.

Fyxer is the clearest. Its help centre article on how drafting works states: “Fyxer never sends drafts automatically – you always review and approve.” Other tools in this category leave pre-written replies waiting in your inbox for you to review and send.

For anything client-facing, draft-only is the safer default. An assistant that sends on your behalf can be genuinely useful for routine scheduling replies, and genuinely damaging on a sensitive thread. Read each vendor’s documentation rather than assuming, because the marketing language of “handles your inbox” covers both behaviours.

Replacement email clients

1. Superhuman

Superhuman is the speed product: keyboard shortcuts for everything, split inboxes, instant search and AI auto-drafts written in your voice. Its product page describes it as “built for teams that use Gmail or Outlook”, so unlike some tools here it is not Gmail-only.

The ownership and pricing both changed. Grammarly announced its intent to acquire Superhuman on 1 July 2025; neither company published a deal value. On 29 October 2025 Grammarly announced it was “changing its company name to Superhuman, uniting Grammarly, Coda, and Superhuman Mail under one brand”. The same name now refers to both the email client and the wider suite, which is a genuine source of confusion when reading pricing pages.

The Superhuman Mail pricing page lists Starter at $30 per member per month billed monthly, or $25 billed annually, and Business at $40 monthly, or $33 annually, with annual advertised as 17% off and a further 15% off Business for teams of five or more. Enterprise is quoted on request.

Separately, the Superhuman Suite bundles Grammarly, Coda and Go: Free at $0, Pro at $12 per member per month billed annually or $15 monthly, Business at $33 annually or $40 monthly, and Enterprise custom. Superhuman Mail is not included in the Free or Pro suite tiers — it appears only from Business upward.

The practical warning follows from that: Mail and the Suite each have a plan called Business, and both are priced at $33 annually. If a quote looks like it covers everything, confirm which Business it is. Our Grammarly review covers the writing side of the same suite.

Suits: founders, executives and sales staff processing high volume daily, where triage speed compounds.

2. Shortwave

Shortwave is the Gmail-native alternative, with thread summaries, AI drafting, strong search and automation. Its AI assistant runs on Claude models, with the intelligence level rising by tier.

A free plan exists: Shortwave’s billing documentation states that “Shortwave is free to get started” and that “the free plan gives access to most of our productivity features and capabilities, including the Shortwave AI executive assistant”. Two things constrain it. Paid plans add the ability to import your full email history and use advanced AI search and writing personalisation. And the pricing page lists “No ‘Sent with Shortwave’ signature” as a paid feature, described as letting you “remove the ‘Sent with Shortwave’ tagline from the emails you send” — so the tagline is on by default.

It is not the cheap alternative it used to be. The pricing page’s business view lists Business at $30 per seat per month, Premier at $45 and Max at $120, alongside a 14-day free trial. Shortwave Business therefore costs the same monthly as Superhuman Mail Starter rather than a fraction of it, and its AI usage is metered by tier: Business is described as roughly 150–300 standard-intelligence AI requests a day, with Premier at 2x and Max at 6x that, noting that “quota usage varies based on the complexity of the request”. The page also offers an individual view whose prices are rendered in the browser rather than published in the page source.

It is Gmail-centred, so Outlook users should check provider support before committing.

Suits: Gmail users who want an AI-native client with a usable free tier to test first.

Layers on your existing inbox

3. SaneBox

SaneBox is the oldest approach here and does one job: it filters. Unimportant mail is moved out of the inbox into folders you review later, learning from what you actually open and answer. It works with essentially any email provider because it operates at the mail-server level rather than as an app.

It is not an AI assistant in the modern sense, and it is worth being clear about that: no drafting, no summarisation, no reply suggestions. If your problem is volume rather than writing, that focus is the point.

It is also by some distance the cheapest tool here. Its pricing page advertises “Free for 7 days”, then, on two-year billing, Snack at $2.04 a month for 1 email account and 2 features, Lunch at $3.50 for 2 accounts and 6 features, and Dinner at $9.96 for 4 accounts and all features. The page also offers annual and monthly billing, priced higher.

Suits: people whose problem is inbox noise rather than writing, and who do not want to change email clients.

4. Fyxer AI

Fyxer sits on top of Gmail or Outlook, sorting the inbox into categories, drafting replies in your writing style and taking meeting notes. It is the closest thing here to a delegated assistant that does not require switching clients.

Its pricing page lists Starter at $22.50 per user per month billed annually, or $30 billed monthly; Professional at $37.50 annually, or $50 monthly; and Enterprise at bespoke pricing with a 50-member minimum. Starter and Professional both carry a 7-day free trial.

As noted above, Fyxer documents that it drafts but never sends, which is worth knowing in both directions: safer for client work, less autonomous than the marketing implies.

Suits: professionals who want drafting and triage without leaving Gmail or Outlook.

Built into your platform

5. Gemini in Gmail

Drafting, rewriting, tone adjustment and thread summarisation inside Gmail itself, with no separate app. Because Google lists Gemini in Workspace apps as part of the Standard and higher SKUs rather than charging a distinct AI fee, it is the cheapest capable option for most Workspace customers — effectively free at the point of use.

What it lacks is the triage layer. It helps you write; it does not decide what deserves your attention.

6. Microsoft Copilot in Outlook

The Microsoft equivalent, with the advantage of context from across Microsoft 365: documents, calendar and Teams alongside mail. For organisations already standardised on Microsoft, that context is the differentiator.

The cost structure is less simple than Google’s. Because Copilot is an add-on on top of a qualifying licence rather than an inclusion, confirm what your organisation actually holds before assuming access. Our guide to AI productivity tools covers the wider Microsoft AI packaging.

Comparison

Vendor-published figures as of September 2026, linked in the sections above.

There is no writing-quality column. No vendor publishes a reproducible measure of draft quality, and at least one of them, Shortwave, runs on third-party frontier models (Claude), so the practical differentiators are triage and workflow rather than prose.

The entry-tier trap

One pattern runs through this category and costs people money: the advertised entry tier is frequently not the tier containing the feature you are buying for.

Superhuman is the clearest example. The Suite Pro plan at $12 a member does not include Mail at all — Mail starts at Suite Business, $33 annually. Shortwave’s free plan puts a “Sent with Shortwave’ tagline on your outgoing mail unless you pay to remove it. SaneBox’s $2.04 tier covers one email account and two of its features, not all of them. And Microsoft’s Copilot is an add-on rather than an inclusion on most licences.

Before subscribing, confirm three things: which named plan contains the specific feature you are buying for, whether the price you were quoted is monthly or annual, and what the renewal terms are after a trial. Several tools here run trials that convert automatically.

How to choose

Check your existing plan first. If you have Workspace Standard or above, or a Microsoft 365 licence with the Copilot add-on, you may already have drafting and summaries at no extra cost.

Your problem is volume, not writing: a filtering layer starts at $2.04 a month on two-year billing and does not require changing anything about your setup.

You live in your inbox all day: a replacement client is where the time savings compound, and the $25–$40 premium is easier to justify the more of your day is spent triaging.

You want drafting without switching apps: an inbox layer sits on Gmail or Outlook and leaves your setup intact, from $22.50 a user on annual billing.

You are on Outlook: check provider support first, because it narrows the field before any other consideration. Superhuman Mail states Gmail and Outlook; Shortwave is Gmail-centred; SaneBox works at the server level with almost any provider.

You handle confidential correspondence: check where mail is processed and whether it is used for training, and prefer draft-only behaviour over anything that sends autonomously.

Related guides

• Best AI Writing Tools in 2026
• Grammarly Review 2026
• Best AI Productivity Tools in 2026
• Best AI Meeting Assistants in 2026
• Best AI CRM Tools in 2026
• Best AI Chatbots in 2026

Frequently asked questions

Do I need to pay for an AI email assistant?

Often not. Google lists Gemini in Workspace apps as included in Business Standard and above, and Copilot is available on Microsoft 365 as an add-on, so drafting and summaries may already be covered. Paid tools add triage, speed and delegation rather than better writing.

What happened to Superhuman?

Grammarly announced its intent to acquire it on 1 July 2025, and on 29 October 2025 renamed itself Superhuman, uniting Grammarly, Coda and Superhuman Mail under one brand. Neither company published a deal value. Superhuman Mail plans are now $25 to $40 per member per month depending on tier and billing.

Will these tools send email for me?

Usually not by default. Fyxer’s help centre is explicit — “Fyxer never sends drafts automatically” — and several tools leave replies waiting for your approval. Autonomy differs by product, so check the documentation rather than the marketing.

Which has a genuinely usable free tier?

Shortwave. Its documentation says the free plan covers most productivity features including the AI assistant; what it does not cover is full history import, advanced AI search, and removing the “Sent with Shortwave” tagline from your outgoing mail. The platform-native options are free at the point of use if your organisation already holds the relevant plan.

What is the cheapest tool here?

SaneBox, at $2.04 a month on two-year billing for one email account and two features. It is also the most limited — it filters, and does not draft or summarise anything.

Is a faster email client worth $30 a month?

It depends on volume. The case rests on triage speed compounding across a heavy inbox, which is why these products target people processing dozens of messages daily. At normal volume, the option already included in your existing plan is difficult to beat on value.

Conclusion

Start with what you already pay for. Drafting and thread summaries come with Google Workspace from the Standard tier upward and are available on Microsoft 365 as an add-on, and for most people that covers the writing problem entirely.

Pay for a dedicated tool when the problem is something those do not solve: triage at volume, keyboard-speed processing, or delegated drafting inside your existing inbox. Then check two details before subscribing — which named plan actually contains the feature you want, and whether the tool drafts for your approval or acts on its own. Those two answers matter more than any comparison of writing quality.