The best AI inbox tools for small teams in 2026

Short answer

For a team of two to ten people sharing one mailbox, Missive is the best AI inbox tool in 2026: real collaboration inside the thread, generic IMAP support and 14 USD per user and month billed yearly. Front wins if you need routing, SLAs and a selectable EU hosting region, and BoxBee wins if the deciding question is where the mail text is processed, as long as you accept that it is not a shared inbox.

How we ranked

Five criteria, measurable, fixed before any product appears below. A shared inbox is a different purchase from a personal AI client, so the weights are different from our ranking of AI email clients.

1. Where is the mail text processed, and under which jurisdiction? The entity that holds the bytes, and the law that applies to it.
2. Is a European model provider used? Mistral and the EU regions of the hyperscalers count. OpenAI, Anthropic and Google in a US region do not.
3. Price per seat and month at three seats, net, cheapest paid plan, USD converted at 1 USD = 0.92 EUR, including minimum seat counts.
4. Does the team genuinely share one inbox? Assignment, internal comments on the thread, collision handling so two people do not answer the same customer.
5. Does it work on the mailboxes you already have? Google Workspace, Microsoft 365 or generic IMAP, without a migration.

One result is worth stating before you read on. BoxBee wins criteria 1, 2 and 5 outright and is the only product here with a European model provider, but it loses criterion 4 completely: the Team tier gives you shared administration and billing, not a shared inbox. It has no assignment, no internal thread comments and no collision handling. We rank it third rather than first for that reason, and we say so because that is the only version of this list worth publishing.

The seven tools, compared

1. Missive, the cheapest real shared inbox

Missive puts internal chat inside the conversation, so a colleague discusses a customer mail next to the mail rather than in a forwarded thread. Assignment is clean, collision handling works, and the same inbox takes WhatsApp, Messenger, Instagram and SMS. Starter is 14 USD per user and month billed yearly for up to five users, which is the lowest entry price in this list, and the trial is 30 days without a card. The AI is deliberately bring-your-own: you pick OpenAI, Anthropic Claude or Google Gemini and supply a key, which means you control the processor and the cost. The documentation is honest that email content is sent to the provider you chose and that OpenAI and Anthropic may retain API data for up to 30 days for abuse monitoring. Every sub-processor on the published GDPR page is in the United States and the DPA arrives by email on request.

2. Front, the one with an EU hosting region

Front is the enterprise end of this market and it is the only vendor here that lets you choose where the data lives: it supports hosting in the US or the EU. Its sub-processor list is dated, itemised and names OpenAI, Google, Azure, AWS and TypeSafe AI with the purpose AI-enabled functionality, tying the processing location to the region you picked. The DPA is published, and it carries SOC 2 Type II and ISO 27001. Routing, SLA rules and omnichannel coverage are in a different league from Missive's. The price is the catch. Starter at 25 USD per seat is limited to ten seats and a single channel type, Professional is 65 USD, and Copilot is another 20 USD per seat unless you are on Enterprise. Autopilot is billed per conversation from 0.39 USD, so heavy automation is hard to budget.

3. BoxBee, best on data protection, not a shared inbox

BoxBee is the only product in this list that does not transmit the message body at all. Its published privacy policy keeps subject, body and attachments on the device in the operating system keystore, and names one AI sub-processor: Mistral AI in Paris, hosted in the EU region, contractually without training. The controller sits in Luxembourg, so the GDPR applies directly rather than through an adequacy decision. For a small European firm where the works council or the data protection officer decides, nothing else here is close. What you do not get is the thing this list is about. The Team tier at 29.00 EUR per seat with a three seat minimum adds shared administration, not a shared mailbox, so there is no assignment, no internal comment on a thread and no collision handling. It is also the most expensive entry price here. Buy it as three good personal clients with one invoice and a defensible processing chain, and read what a DPA has to say before you sign.

4. Hiver, the shared inbox your staff already know

Hiver's advantage is that there is nothing to adopt: the shared inbox is Gmail, with queues, assignment and SLAs added by a Chrome extension. For the Gmail variant the vendor states it does not store mail permanently and that storage never exceeds one hour for 99 percent of messages, which is a genuinely unusual claim in this category. Hiver Omni, the standalone app, adds Outlook, Zoho, chat, voice and WhatsApp, and does store mail content. Growth is 25 USD per user and month on annual billing with a two seat minimum. The data protection picture is the weakness: everything sits on AWS in Oregon with no EU option, staff in India may access it, the privacy policy lists the message body and attachments among the data sent to AI providers, and the DPA is request only.

5. Gmelius, the budget Gmail shared inbox

Gmelius adds shared labels, kanban boards and email sequences to Gmail from a Swiss vendor, with the entry plan at 19 USD per user and month on annual billing for up to five users. The boards are the reason to pick it: if work arrives as mail and leaves as a task, the pipeline lives where the work is instead of in a second tool. It is Gmail only, the trial is 7 days with no free plan, and the published documentation stops at the pricing page, so a sub-processor list, a hosting statement and a DPA all have to be requested in writing. Treat the AI as automation rather than as a model-driven assistant.

6. Shortwave, the best AI, sold per seat

Shortwave sells Business, Premier and Max per seat, but what you are buying is the best AI search in the category on each person's own Gmail account, not a shared queue. If your team's problem is that nobody can find anything in three years of mail, this is the answer, and no competitor is near it. If the problem is that two people answer the same customer, it is not. Gmail and Google Workspace only, Microsoft 365 explicitly unsupported, data in US data centres, and no published DPA or sub-processor list. At 30 USD per seat it is also the most expensive personal client here. See BoxBee against Shortwave.

7. Spark Mail, the free tier and the EU contract

Spark earns a place for two reasons: a genuine free tier, so a two person team can test the workflow at no cost, and an Irish contracting entity with a published DPA naming the Irish Data Protection Commission. Pro at 19.08 EUR per user and month on annual billing adds shared drafts and delegation. The team layer is the thinnest here, closer to collaboration on drafts than to a queue with ownership. The privacy policy names Azure OpenAI, OpenAI, Anthropic and Google Vertex AI, mail content including attachments goes to them, and the DPA states that the full sub-processor list is deliberately not public.

How to choose in one pass

Start with criterion 4, because it is binary. If two people must never answer the same customer twice, you need Missive, Front, Hiver or Gmelius, and the rest of the list is out whatever else it does well. Then apply criterion 1. If the processing location is a hard constraint, you are down to Front with the EU region, and you should expect to pay Professional prices for it. If the location is a hard constraint and the budget is small, the honest answer is that no shared inbox in this list meets both, and the workable compromise is three BoxBee seats plus a discipline about who owns which sender.

On price at three seats, the monthly spread is real: Missive 38.64 EUR, Gmelius 52.44 EUR, Hiver and Front 69.00 EUR, Shortwave 82.80 EUR, BoxBee 87.00 EUR. The cheapest option is also the one with the best collaboration model, which does not happen often in software.

For what these tools genuinely do and do not do, see what an AI email assistant actually does. Vendors can get listed and be assessed against the same five criteria.