Running a Shared Team Inbox with Kanban

A shared team inbox (support@, hello@, sales@) starts simple and decays fast. Two people answer the same customer within minutes of each other. Something urgent sits untouched for two days because everyone assumed someone else had it. And the only signal anyone has, read versus unread, lies constantly.

It lies worse than you might think. In a shared IMAP mailbox, read state belongs to the mailbox, not to the person. The moment anyone opens a message it shows as read for the entire team, whether or not anybody intends to answer it. “Unread” was never a to-do list; in a shared inbox it isn’t even a reliable “nobody’s seen this yet”.

The underlying problem is that a shared inbox needs states a personal one doesn’t: new, someone’s on it, waiting on the customer, done. Two honest ways exist to get those states. You can buy a tool that adds a team layer on top of email, or you can run the mailbox itself with folders and a convention. This post covers both, because they suit different teams.

First, the honest framing

Kanmail sits firmly in the second camp. It’s a single-user desktop email client. There is no team layer: no assignments, no “Sam is replying” warnings, no internal comments on a thread. What it gives you is a kanban board view of a mailbox your team already shares, with each person connecting to the same IMAP account from their own machine.

That sounds thin until you remember what IMAP actually does. Folders and flags live on the server. When one person drags a message into another folder, that move happens server-side, and everyone else connected to the mailbox sees it when their client next syncs. Ordinary, boring, thirty-year-old plumbing, and it’s enough to build a workable shared workflow on.

The board model on a plain shared mailbox

Set up folders in the shared account and show them as columns (in Kanmail, columns are just your folders):

• Inbox stays as “new and unclaimed”
• One claimed folder per person: Nick, Sam, Priya
• Waiting on customer
• Done (or just Archive)

The per-person folders are the trick. Claiming a conversation means dragging it into your own column, which files it into your named folder on the server. Anyone who opens the board sees at a glance what’s unclaimed, who’s holding what, and what’s stalled waiting on a reply. No stand-up, no “who’s got this one?” message in Slack.

One rule makes it work: drag before you type. A card in your column is your card. Sync isn’t instantaneous (clients poll the server rather than watching a live cursor), so the claim can take a minute to appear on a colleague’s board. For a team of two to five people handling a few dozen messages a day, that window is small enough that double replies mostly disappear. Mostly.

What this approach won’t give you

Worth being blunt, because the failure modes of shared mailboxes are well known and a folder convention only fixes some of them.

There is no collision detection. If two people open the same unclaimed message at the same moment and both skip the drag-first rule, nothing warns them. Dedicated tools solve this properly; a convention only shrinks it.

There are no internal notes. If you want to discuss a thread before replying, that conversation happens somewhere else.

There’s no reporting, no SLA timers, no auto-assignment. If a manager needs a chart of response times, this isn’t the setup.

Everyone shares the credentials, usually an app password for the shared account. Fine at three people. Ugly at fifteen, and a genuine offboarding chore.

And one Google-specific catch: Gmail delegation only works inside the Gmail web interface. A delegate can’t connect to the delegated mailbox over IMAP, so for a Google-hosted shared address each teammate signs into the shared account itself (with its own app password or OAuth) rather than via delegation.

The free middle ground: Google Collaborative Inbox

If you’re on Google Workspace already, Google Groups Collaborative Inbox is included and adds real assignment: members can take a conversation, assign it to someone, and mark it complete.

The catch is where it lives. All of that only works in the Groups web interface at groups.google.com, not in Gmail, so your team triages in one tab and replies in another. It also has no collision detection, no shared drafts, and famously clunky ergonomics. It’s a reasonable answer for a low-volume address nobody wants to spend money on, and most teams that lean on it daily end up wanting out.

When you should just buy Front or Missive

Some teams should skip everything above and pay for a real shared inbox tool. Current pricing as of mid-2026:

• Front runs $25 per seat per month on Starter (capped at 10 seats and a single channel) up to $65 on Professional and $105 on Enterprise, billed annually.
• Missive is free for up to 3 users, then $14 to $36 per user per month billed yearly. For a tiny team the free tier is genuinely generous.
• Help Scout has a limited free plan, with paid plans from $25 per user per month.

Buy one of these if any of the following is true: you need hard assignment and collision warnings rather than a convention, you want internal notes on threads, you need reporting or SLAs, or the team is heading past five or six people. At that point the tooling earns its subscription and you should stop fighting it.

Then run the maths the other way. Three people on Front Professional is $195 a month, about $2,340 a year, which is a lot of machinery for a founder and two teammates answering forty messages a day. For that team, columns, visible ownership, and a waiting state cover ninety percent of the problem. Kanmail is a one-off purchase per person, the mail never touches a third-party server, and if you outgrow the setup you’ve lost nothing: the messages are sitting in ordinary IMAP folders you can point any tool at later.

Setting it up

The whole thing takes about half an hour:

1. Each teammate connects the shared address over IMAP from their own machine, using the shared account’s app password.
2. Create the folders in the shared account: one per person, plus Waiting and Done.
3. Each person adds those folders as columns on their board. Board layouts are configured per install, but the folders (and every card move) live on the server, so everyone is looking at the same underlying state.
4. Colour-code your most important senders so key customers stand out in any column.
5. Agree the one rule: drag it to your column before you start typing.

That’s a working shared team inbox you can stand up this afternoon, with no per-seat fee ticking in the background. And if it stops being enough, you’ll know exactly which missing feature you’re paying Front for.