Alternatives to Sendmux

HEY Email is 37signals' rethink of email: a Screener vets first-time senders so only people you approve ever reach your Imbox.

Shortwave is an AI email assistant and native client where Claude 4.6 agents manage triage, drafting, scheduling, and search in your inbox.

Newton Mail is a paid, cross-platform email client with automatic read receipts, snooze, send later, and shared team inboxes for Gmail, Outlook, and IMAP.

Superhuman is AI email, docs, and a proactive Go assistant whose agents run inside Slack and your other work apps.

SaneBox AI email management sorts your inbox into smart folders so you waste fewer hours on low-priority mail.

Jace is an AI executive assistant that sits on top of Gmail and Outlook to organize your inbox, draft replies with full context, and run email-triggered

AI email assistant that triages your inbox and drafts replies for $8.25/month.

A persistent-memory AI agent OS that runs your email, files, and research on a schedule.

Town gives you a personal AI assistant that studies how you work, then handles your email, meetings, and recurring admin on its own.

Wuko AI is an email-based summarizer: send any article URL to read@wuko.ai and get an AI summary plus follow-up Q&A in seconds, no signup.

Missive + AI folds GPT-powered summarize, translate, and reply drafting into a shared team inbox for email, SMS, WhatsApp, and chat.

Canary Mail is an AI email client with an on-device Copilot, PGP encryption, and a unified inbox for Mac, iOS, Windows, and Android.

Shortwave is an AI email assistant for Gmail that triages, drafts, schedules, and searches your inbox with Claude 4.6 models.

Free iOS and Android email app that merges Gmail, Outlook, Yahoo, iCloud and Exchange into one inbox with 65GB of mail storage.

AI-first email app that turns your inbox into a chat-style hub for email, docs, tasks, and calls

Stamp is an AI secretary for email and calendar that drafts replies in your voice, prioritizes your inbox, and books meetings.

AI email assistant and tracking extension that runs inside Apple Mail, Gmail, and Outlook instead of replacing your inbox.

Zinley is an autonomous personal agent that answers calls, handles email, and follows up without you prompting every step.

Free email with AI compose, thread summaries, and a Planner that turns messages into tasks and calendar events.

AI Gmail add-on that auto-drafts contextual email replies in your voice, ready for your review before sending

Mailopoly is an AI email assistant that folds email and business messaging into one Poly-powered inbox.

Replai is an AI email assistant that learns your writing style and drafts replies in your own voice, plus inbox triage and meeting notes.

Cora is an autonomous AI email assistant that connects to Gmail, drafts replies in your voice, and sends you twice-daily briefs.

Personal AI work bots, one per person, each running on its own desktop and pausing for your approval before anything sends.

Lindy is a Slack-native AI teammate that runs agentic workflows across 1,500+ integrations and answers your @mentions in-thread.

End-to-end encrypted email from Switzerland, bundled with VPN, Drive, and Pass

Microsoft Outlook: unified email, calendar, contacts, and to-do across accounts, from free web and mobile apps to Microsoft 365 desktop clients.

Carly AI is an email assistant you CC to delegate scheduling, follow-ups, CRM updates, and plain-English workflows.

Spark Mail is a cross-platform AI email client that sorts, summarizes, and drafts across Gmail, Outlook, Exchange, iCloud, Yahoo, and IMAP.

Dimension was a proactive AI coworker for email, Slack and calendar work — now winding down May 20, 2026.