Honest comparison
Shortwave Alternative: A Unified Inbox for Every Provider, Not Just Gmail
Connect every mailbox you own to one board, in the browser, and let AI read each message to categorize it and flag spam before you open it.
Any IMAP provider · AI category + spam per message · Two-way sync
In short
Shortwave is an AI-native email client for Gmail, with a conversational assistant, semantic search over your whole history, and AI that drafts in your voice. Its hard limit is that it works only with Gmail and Google Workspace: Outlook, iCloud, Yahoo, and any IMAP account are left out, and its unified inbox is really other mail forwarded into Gmail. Inboxes is provider-agnostic: it connects any IMAP mailbox to one browser board and has an AI model categorize each message and flag spam. If you are all-in on Gmail and want the deepest AI, Shortwave is excellent. If your mail is spread across providers, that is where Inboxes fits.
The difference
Where Inboxes and Shortwave actually diverge
Shortwave has arguably the deepest AI of any email client. Its assistant will reorganize your inbox on command, its semantic search answers questions across years of mail, Ghostwriter drafts replies in your tone from your own sent history, and auto-labels are plain-English rules the AI runs for you. It has native desktop and mobile apps. The reason people search for an alternative is almost always the same one: Shortwave works only with Gmail and Google Workspace. As of mid-2026 there is no Outlook, no Microsoft 365, no iCloud, no Yahoo, and no generic IMAP, and the unified inbox it advertises is other accounts forwarded into your Gmail, which means you cannot cleanly send from those addresses. Inboxes is built the opposite way. It sits above the providers: connect Gmail, Outlook, iCloud, Yahoo, or mail on your own domain over IMAP, and every account lands on one board where an AI model categorizes each message and flags spam. Inboxes does not draft your email the way Shortwave does. It reads and sorts across every mailbox, which is the job Shortwave cannot do once your mail is not all in Gmail.
Side by side
Inboxes vs Shortwave
| Capability | Inboxes | Shortwave |
|---|---|---|
| Unified inbox across every account | Yes | Via forwarding into Gmail only |
| Any IMAP mailbox (Gmail, Outlook, iCloud, Yahoo, own domain) | Yes | Gmail and Google Workspace only |
| AI categorizes every message automatically | Yes | Yes |
| AI spam detection on top of the provider filter | Yes | No |
| AI that drafts and rewrites your replies | No | Yes |
| Conversational AI assistant and semantic search | No | Yes |
| Free plan (no trial) | No | No |
| Entry price | $29/mo flat | From $30/seat/mo, 14-day trial |
Pricing and features verified from each vendor's public pricing page in July 2026, and quoted in the currency the vendor publishes. Both products change, so check the current page before you buy.
// Where Shortwave wins
Shortwave is the better choice for a clear group of people, so here it is. If you are entirely on Gmail or Google Workspace and want an AI assistant that reorganizes your inbox, semantic search across years of mail, or AI that drafts replies in your own tone, Shortwave does all of that and does it as well as anyone. We do not write your email; our AI reads and sorts it. Choose Inboxes only if you need a true unified inbox across providers beyond Gmail, from a browser, sorted automatically.
FAQ
Questions people ask before switching
What is the best Shortwave alternative?
If you left Shortwave because it only works with Gmail, the alternative you want supports more providers: Inboxes connects any IMAP mailbox to one AI-sorted board in the browser. If you want another AI client and you are staying on Gmail, Superhuman is the usual premium comparison, and Missive supports multiple providers for teams.
Is Shortwave only for Gmail?
Yes. As of mid-2026 Shortwave connects only Gmail and Google Workspace accounts. Outlook, iCloud, Yahoo, Fastmail, and generic IMAP are not supported natively, so non-Gmail mail has to be forwarded in. Inboxes connects any IMAP mailbox directly, which is the main reason people move between the two.
Is Shortwave free?
No. Shortwave is paid only, with a 14-day trial and no permanent free plan. Its Business plan is $30 per seat per month, with higher Premier and Max tiers for heavier AI use. Inboxes is also paid only, one flat plan from $29 a month, with no free tier either.
Does Shortwave have a unified inbox?
Only through forwarding. Shortwave own docs describe a unified inbox as other accounts forwarded into your Gmail, which means you cannot send from those addresses cleanly. Inboxes keeps every account distinct on one board, so replies leave from the right address and threads and search cover all of them.
Which is better, Shortwave or Superhuman?
Both are Gmail-friendly AI clients: Shortwave leans into a Claude-powered assistant and semantic search, Superhuman into keyboard speed, and Superhuman also supports Outlook. Neither offers a true unified inbox across many providers, which is the gap Inboxes fills for mail spread across Gmail, Outlook, iCloud, and your own domain.
Keep comparing
More on running every mailbox from one place
Put every mailbox on one sorted board
Connect your accounts over IMAP and let the AI categorize and de-spam your mail from the first message.