Overview

The assistant can turn keywords into a draft, prepare a reply from details you provide, and adjust generated text’s format, length, style, tone, and language. It can also summarize selected emails and identify to-dos for Mailbutler Tasks. Smart Improve suggests spelling and grammar changes to a written draft. Mailbutler says the assistant uses OpenAI GPT-4o.

This is a preparation and organization aid, not an automatic sender: you still review and send replies. Summaries and task identification make it more useful for keeping up with a busy inbox than a tool focused only on drafting, though the feature set is tied to Mailbutler’s paid tiers after the 14-day trial.

Key features

Compose and reply: Draft from keywords or supply context for a generated response. This can speed up routine correspondence while leaving the final wording and send decision to you.
Writing controls: Change format, length, style, tone, and language. That range is useful when one draft needs a different register or level of detail.
Summaries and tasks: Summarize selected messages and find to-dos to add to Mailbutler Tasks. The workflow can surface follow-up work without claiming to automate it.
Improve drafts: Smart Improve suggests spelling and grammar improvements, a focused check rather than a substitute for reviewing the message yourself.

Mailbutler says it is ISO/IEC 27001 certified and GDPR compliant, and that backend data is encrypted. For Smart Assistant, the email body and subject are processed by Microsoft Azure OpenAI Service in the EU, with personal data redacted before submission to the underlying model. Mailbutler says its support team answers queries 24/7 and provides a Support Center.

Pricing

The Starter plan is free forever, but sent emails carry a visible Mailbutler watermark and it does not include Smart Assistant. The 14-day trial includes Smart Assistant; after that, the assistant requires Smart or Business.

Professional: $7.00 USD per month billed annually, or $9.00 USD per month with monthly billing. It covers email tracking, templates and mail merge, inbox collaboration, and signature marketing, but not Smart Assistant. Choose it for Mailbutler’s email workflow tools without AI drafting and summaries.
Smart: $11.00 USD per month per user with yearly billing, or $14.00 USD per month per user with monthly billing. It adds Smart Assistant and Smart Follow-ups alongside tracking, mail merge, and inbox collaboration. This is the entry point for readers who want the AI features.
Business: $24.00 USD per month per user with yearly billing, or $32.00 USD per month per user with monthly billing. It includes Smart Assistant and Smart Follow-ups plus CRM tracking sync, custom subdomain, and IP blacklisting. It fits teams needing those business-oriented additions; otherwise, Smart is the less costly way to get the assistant.

The plan information also gives Professional at $7.00 USD per month billed annually, Smart at $11.00 USD per month billed annually, and Business at $24.00 USD per month billed annually; the per-user billing terms are stated for the detailed yearly and monthly options above. No seat or usage quota is stated for Smart Assistant.

Platforms

Mailbutler lists Android, iOS, Linux, macOS, web, Windows, and an extension among its platforms, but client compatibility varies. Apple Mail support is listed for macOS Tahoe, Sequoia, Sonoma, and Ventura; Gmail works on macOS, Windows, and Linux; and mobile apps require iOS 15 or later or Android 7 or later. The broad platform list should not be read as every email client being supported on every operating system.

Mail Merge can use Apple, Google, or Outlook Contacts, HubSpot or Salesforce, and CSV data. CRM tracking sync is listed for HubSpot and Salesforce, a distinction that matters if CRM integration is the reason to choose Business.

Who it's for

Smart Assistant is a strong fit for people already using Apple Mail, Gmail, or Outlook who want one place to draft, refine, summarize, and turn email into tasks. It is less suitable if you need automatic sending, want the AI features on a free plan, or rely on an email-client and operating-system combination outside the stated compatibility.

Pros and cons

Pro: Drafting, adjustable writing, summaries, task identification, and grammar suggestions cover several stages of handling email.
Pro: EU processing through Microsoft Azure OpenAI Service, redaction before model submission, encryption, and stated GDPR compliance address important privacy concerns.
Con: Smart Assistant is not part of the free Starter plan and requires Smart or Business after a 14-day trial.
Con: Replies are not sent automatically, so users must still review and send them.
Con: Compatibility depends on both the email client and operating system, limiting its reach despite a broad platform list.

Alternatives

For a narrower focus on email tracking, Mailtrack has a free plan with unlimited tracked emails, first-open logging, a promotional signature, 100 campaign emails, and 10 link-tracked emails; it does not offer a free trial. Choose it when tracking is the priority rather than AI writing and task handling. Boomerang is another freemium option, with a free Basic plan limited to 10 message credits per month and including Gmail/G Suite, Send Later, and Boomerang Reminders; it may suit readers who want those scheduling and reminder tools.

For broader category browsing, see AI Email Assistants, Email Tracking Software, Sales Email Tracking Software, or Email clients. KudosCRM, Streak, Close, Salesmate, Salesflare, and Salesforce Sales Cloud are other options to compare.

Verdict

Choose Mailbutler Smart Assistant if you use a supported client and want drafting, summaries, and task detection together, with privacy safeguards Mailbutler describes. Look elsewhere if a free AI tier, automatic sending, or broader client compatibility is essential; the trial is short, and ongoing assistant access starts with a paid Smart subscription.

	Mailbutler Smart Assistant	Opterius Mail
Free plan	Yes	Yes
Free trial	Yes
Paid from	$7/mo	Free
Platforms	Android, extension, iOS, Linux, macOS, Web, Windows	Web
Free plan	Yes	Yes
Paid from	$4/user/mo
Inbox triage	Yes
AI reply drafting	Yes
Automatic sending	No
Thread summaries	Yes
Follow-up actions	Yes
App coverage		web

Mailbutler Smart Assistant vs Opterius Mail

Mailbutler Smart Assistant

Opterius Mail