Email Platform
Cairn
Your domain. Your infrastructure.
A cairn is the stack of stones that marks the trail — email that's yours, marking the way. Not rented. Not borrowed. Not lost if you leave.
Live — running our own company's mail todayOwnership
Most business email is rented.
Your address is on their domain. Your data lives on their servers. And the price goes up whenever they decide it should. Switch providers and your history goes with you — if they'll let you take it.
The Mail
Where work arrives.
A full webmail client at your domain. Threads, search, filters, and the AI triage tools you'd expect from a modern inbox — with everything running on your infrastructure.
Deliverability
Self-hosted doesn't mean ending up in spam.
SPF, DKIM, and DMARC — the three authentication records that tell every inbox your mail is real — configured and managed. Sending rails run through verified infrastructure with strong reputation scores. Mail that actually lands.
Your domain, your inbox, your data — no dependency on Google's pricing decisions or platform lock-in.
Add team addresses, aliases, and departments without watching costs scale with every hire.
SPF, DKIM, DMARC, and sending reputation configured and maintained — so your mail actually arrives.
DNS, migration, and ongoing infrastructure handled for you. Not a DIY mail server you configure alone.
Fully managed
Set up for you, cared for forever.
We migrate your existing mail, configure your MX records, set up authentication, and hand you a working inbox. After that: updates, monitoring, and deliverability are on us. You never have to think about your email infrastructure again.
We move your existing mail history, contacts, and folders — nothing gets left behind.
SPF, DKIM, DMARC, and MX records set up correctly the first time. No guessing.
Security patches and feature updates handled on our schedule, not yours.
The math
Stop paying per mailbox.
20 mailboxes on your domain. Cap active — your bill stops at $49/mo. Here’s what each option costs per month:
At 20 mailboxes, Google/Microsoft charges $7/seat and keeps climbing. Cairn’s bill stopped at $49 — $91/mo less. Add more mailboxes at no extra charge.
Illustrative example only. Google Workspace Business Starter ~$7/user/mo; Microsoft 365 Business Basic ~$6/user/mo; higher tiers $12–22/user. Cairn $4/seat, $49/mo cap (1–49 seats), $99/mo flat (50–199 seats) are founding-rate preview pricing — final pricing agreed in writing before engagement. 200+ seats: contact us for enterprise pricing.
Scales with you
Every tier of your team, addressed.
Start with one mailbox. Add team addresses as you grow — guides, ops, billing, bookings, hello. All on the same infrastructure, all under one flat rate. Pair with Outpost to give your members a real address at your domain — one more reason to stay.
We run the email machinery.
Your mail on your infrastructure.
Not software you configure and maintain — we handle the DNS, the server, the deliverability, and the monitoring. Your mail still lands in your inbox; your domain, your contacts, and your send reputation stay yours. We keep the infrastructure running at a flat monthly price; you just use it.
Ready to move your mail home?
Tell us about your current setup. We'll scope the migration and come back with a clear picture of what it takes — and what it costs.
Works well with
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