🔒 Personal
Only you
A private thought attached to the thread.
"Remember to call Sarah tomorrow."
PlainMailOS · Email, operated
Your inbox is full of conversations.
Your work is hidden inside them.
Make your email intelligent. PlainMailOS turns the chaos of everyday email into something you can actually manage — understanding conversations, tracking commitments, identifying what needs a response, and keeping important work from disappearing into your inbox.
Stop managing messages. Start managing what they mean.
For individuals and teams·Outlook · IMAP · Custom Domains · Gmail coming soon
Inbox
Starred
Sent
Drafts
Sticky Notes
Alerts
Good morning, Kalpesh
4 things need your attention.
Customer waitingSarah is waiting for your reply.
Sarah Johnson
Re: Order #4821 — "Just checking if..."
Rahul Mehta
Contract approval
📝 New sticky note
Rahul mentioned you
"Can we approve this?"
Open thread →
The problem
Is your email
working for you?
You have hundreds — maybe thousands — of emails.
But somewhere inside them are:
A customer waiting for your response
A proposal that needs approval
A payment someone promised to make
A deadline buried three replies deep
A task you agreed to complete
A meeting someone asked you to schedule
A follow-up you forgot to send
A commitment nobody is tracking
Your inbox knows all of this. But your inbox doesn't organize it for you. PlainMailOS does.
What it understands
Your email shouldn't just tell you
what arrived. It should tell you what matters.
PlainMailOS analyzes the structure and meaning of your email conversations to help you understand:
01
Conversations
See the complete story instead of hunting through individual messages.
02
Follow-ups
See which conversations are waiting on you and which are waiting on someone else.
03
Invoices & bills
Pick out the vendor, amount and due date from invoices so nothing goes unpaid.
04
Responses
Know who is waiting for whom — and which conversations need attention.
05
Deadlines
Surface dates and requested completion times, and flag what is overdue before it becomes a problem.
06
Ownership
Understand who is responsible for the next action.
07
Contacts
See who you correspond with and the conversations you have with each of them.
08
Priority
Separate important work from everything else competing for your attention.
From inbox to intelligence
A normal email system sees messages.
PlainMailOS sees work.
A normal email system sees
Message→Message→Message→Message
PlainMailOS sees
Message
↓
Identity
↓
Conversation
↓
Facts
↓
Commitments
↓
Tasks
↓
Deadlines
↓
Responsibility
↓
Current State
↓
Next Action
That's the difference. Your email becomes a structured source of work intelligence.
Conversation intelligence
Never lose the thread
again.
A conversation rarely lives in one message. People reply from different devices. Messages move between folders. Subjects change. Threads split. People are added and removed. Different mailboxes may contain different parts of the same conversation.
PlainMailOS reconstructs conversations using the underlying signals in your email — not simply the way your inbox happens to display them.
Instead of asking
"Where was that email?"
→
You can ask
"What is happening with this conversation?"
Structured extraction
Know what
is waiting.
Someone says:
"Can you send the revised proposal by Friday?"
PlainMailOS can recognize the conversation as more than an email.
It can become:
Request
Revised proposal requested
Responsibility
You
Deadline
Friday
Status
Waiting / Open
Next action
Send revised proposal
The work was already in your email. PlainMailOS makes it visible.
Signal separation
Your inbox is not a task list.
And it shouldn't have to be.
Email contains many different kinds of information:
RequestsRepliesApprovalsPaymentsDeadlinesMeetingsTasksCustomer conversationsNotificationsCommitmentsFollow-ups
PlainMailOS separates these signals so you can understand what is actually happening.
Built for real organizations
Built for the complexity
of real organizations.
PlainMailOS isn't designed only for a personal inbox. It is being designed around a deterministic email intelligence architecture capable of handling:
Multiple providersShared mailboxesAliasesDuplicate messagesCross-mailbox conversationsComplex organizational relationshipsLong-running conversations
Every message needs to be identifiable. Every decision needs evidence. Every result needs to be explainable.
Deterministic by design
Same evidence.
Same result. Every time.
PlainMailOS is built around explicit rules rather than allowing the system to arbitrarily reinterpret the same email differently from one execution to another.
Every important determination
Traces back to the underlying message, headers, identity information, conversation structure, facts, and rules that produced it.
No mysteryEvery rule-based decision explainedNo guessing when the evidence isn't there
When information is insufficient, the system can preserve that uncertainty instead of pretending it knows.
Organizational memory
From email chaos to
organizational memory.
Your company's most important information is already inside email. But today, it is scattered across mailboxes, threads, replies, attachments, headers, contacts, calendars, follow-ups, and human memory.
Imagine opening your inbox and seeing this:
Needs your response
Acme Corp — Revised proposal. Customer is waiting for your response.
Deadline approaching
Website launch — Final assets. Delivery requested Thursday.
Waiting on someone
Invoice #4821. Payment confirmation requested from Finance.
Completed
Contract revision. Approved and sent.
That's an intelligent inbox
Not because it has more emails.
Because it understands what those emails mean.
Your email contains the work. PlainMailOS helps you see it.
The defining feature
Ask your team without
forwarding the email.
CUSTOMER · Sarah Johnson
"Can I get a refund?"
📝 Internal — customer never sees this
Amit → @Rahul
Can we approve this refund?
Rahul → Amit
Yes, up to ₹5,000.
Amit
Done.
You're reading a customer email and need to ask your manager something.
Forward → CC manager → explain context → wait → search for it later
📝 Add a sticky note → @mention → done
No forwarding. No unnecessary CC. No separate Slack message. No losing the context. The note stays attached to the exact thread it belongs to, forever.
@mentionReply trailResolveNotify
Note states
Instead of "did you see my message?" — you see exactly where it stands.
NewReadAcknowledgedRepliedResolved
Not everything is for everyone
👤 Mentioned
Selected people
Visible only to whoever's tagged in.
"@Rahul can you check this?"
👥 Team
The right team
Visible to the relevant department.
"Support team — anyone handled this?"
📬 Mailbox
Shared access
Visible to authorized mailbox users.
support@yourcompany.com
Built for both
Your personal inbox.
Your company's inbox.
For individuals
One person, multiple inboxes, one intelligent workspace — Outlook, IMAP and custom-domain mailboxes all together (Gmail coming soon).
- What needs a reply
- What needs a follow-up
- What can wait
- What's important
- What you've missed
For companies
Companies have departments, shared mailboxes, escalations and hundreds of internal decisions happening around external email. PlainMailOS gives them a structured layer above it.
Company
├── Sales — Rahul, Priya, Amit
├── Support — Sarah, John
└── Finance — Neha, Raj
Shared: support@ · sales@ · billing@
Private email stays private. Shared email stays shared. Access follows permissions, not assumptions.
Security & privacy
Your inbox is not your
company's noticeboard.
PlainMailOS treats mailbox access as a permissioned resource — sensitive infrastructure, not just another database record.
Individuals
A mailbox you connect yourself stays private to you.
Companies
Employees don't automatically gain access to one another's private email.
Shared mailboxes
Explicitly shared, never implicitly open.
Sticky Notes
Defined visibility — enforced by the backend, never hidden by the frontend.
Administration
Company policies determine exactly what each role can see and do.
The difference
Your old inbox
vs. PlainMailOS.
| Traditional email | PlainMailOS |
|---|---|
| Unread count | What needs attention |
| Search messages | Search across every mailbox |
| Star email | Intelligent priority |
| Forward email | Sticky Note |
| CC someone | @mention |
| Remember follow-ups yourself | Follow-up detection |
| Read the entire thread | Conversation intelligence |
| Check inbox constantly | Alerts in one place |
| AI as a separate tool | Optional AI assistance, built in |
| Email is the workspace | Email becomes an action system |
Pricing
Priced per person,
not per mailbox.
Individual
$12/mo
For individuals.
- 1 user
- Multiple email accounts
- Outlook / IMAP (Gmail coming soon)
- Custom domains
- Smart alerts
- Follow-up detection
- Sticky Notes
- Search across mailboxes
Most teams
Professional
$20/mo
+ $10 per seat
For professionals and small teams.
$20 + $10 × 1 seat = $30/mo
Prices in USD, billed monthly; tax added at checkout where it applies. More than 50 seats? Contact us.
- Everything in Individual, plus
- Team collaboration
- Shared mailboxes
- Team Sticky Notes
- Team alerts
- Custom roles
- Team dashboards
Small Business
$30/mo
+ $10 per seat
For growing companies.
$30 + $10 × 1 seat = $40/mo
Prices in USD, billed monthly; tax added at checkout where it applies. More than 50 seats? Contact us.
- Everything in Professional, plus
- Company policies
- Department controls
- Audit log export
Enterprise
Custom
For organizations requiring more.
- Single sign-on (SAML / OIDC) and SCIM
- Custom retention policies
- Priority support
A seat represents a human, not an email address. One employee might connect their personal Outlook, a work IMAP account and a shared sales mailbox — that's still one seat, not three.
Questions
Frequently asked.
Does PlainMailOS replace Gmail or Outlook?+
No. PlainMailOS works with the email accounts you already use — nothing to migrate.
Does PlainMailOS work with Gmail?+
Gmail support is coming soon. Today PlainMailOS connects to Microsoft 365 / Outlook, IMAP and custom-domain mailboxes. Use the form at the bottom of this page and we'll email you the day Gmail launches.
Can I connect multiple email addresses?+
Yes. Every plan can connect several mailboxes; the plans differ by people (seats) and team features.
Can I connect an IMAP account or my own domain?+
Yes to both — compatible IMAP accounts and custom-domain mailboxes are supported.
Can employees see each other's email?+
Not automatically. Private and shared mailboxes are treated differently, and access follows your company's configured permissions.
Can Sticky Notes be seen by customers?+
No. Sticky Notes are internal to PlainMailOS and never leave the platform.
Does PlainMailOS use AI?+
Only if your organization turns it on. PlainMailOS sorts and flags mail with its own rules, without AI. With AI assistance on, it also asks OpenAI to help classify incoming messages; login codes, password resets and clearly identified newsletters are never sent, and OpenAI does not train on the data. Owners can switch it on or off in Settings.
Does AI automatically send emails on my behalf?+
Not by default. Actions that affect your mailbox stay under your control and permissions.
What happens when an employee leaves the company?+
An administrator can revoke their access according to your organization's account and mailbox policies.
Make your email intelligent
Understand the conversation. Track the commitment. Know what happens next.
Stop searching through thousands of messages to reconstruct what happened. Stop relying on memory to remember who owes what. Stop letting important commitments disappear beneath newer emails.
Connect your existing email · Outlook · IMAP · Custom Domains · Gmail coming soon