Self-hosted cold email
Tern sends your sequences from your own inboxes, follows up until somebody answers, then gets out of the way. No contact limits, no per-seat pricing, and your list never leaves your server.
The reason it exists
Every outreach platform meters the one thing you need most: the number of people you are allowed to talk to.
Pay more, get a bigger number. Stop paying, lose the list. Tern was built the other way round. It runs on your server, sends through inboxes you already own, and has no opinion about how many contacts you load into it.
How it works
Google Workspace, or any provider that speaks SMTP and IMAP. Credentials are encrypted before they touch the database, and a connection test tells you straight away whether sending and reading both work.
As many steps as you need, with the wait between them measured in days, hours or minutes. Add variants to test a subject line. Every column in your CSV becomes a variable you can drop into the copy.
Upload a thousand contacts or a hundred thousand. Duplicates are dropped, dead domains are flagged before they cost you a bounce, and anyone on your blocklist is left alone.
Sends go out inside your working hours, spaced like a person typing them, rotating across your inboxes and never past their daily cap. Follow-ups land in the same thread. The moment somebody replies, the sequence stops.
What is inside
Rotation across inboxes, per-inbox daily caps, gradual ramp-up for new mailboxes, and randomised gaps so nothing looks machine-timed.
Multi-step campaigns, A/B variants that can auto-favour the winner, and follow-ups that thread into the original conversation.
IMAP polling separates real replies from bounces and out-of-office notes, then stops the sequence. Read and answer from one inbox.
One-click unsubscribe on every send, automatic blocklisting, and a guard that pauses any inbox whose bounce rate climbs too high.
Opens and clicks recorded with exact timestamps, including repeats, so you can see when somebody actually read it.
Multi-tenant from the first line, an API behind every screen, and your list sitting on a server you control.
What it does not do
No warmup pool. No lead database. No AI writing your emails for you.
Each of those is a product in its own right, and bolting a shallow version of it onto a sending engine would make the sending engine worse. Tern does one job properly and expects you to bring the judgement.
Connect an inbox, write a sequence, and let it work through the list at a pace that keeps you out of the spam folder.
Open the app