Set a Signature for a Whole Domain
Want every email your team sends from yourcompany.com to end with the same sign-off? Open the Signature tab on the domain and you can set it once, for everyone, instead of asking each person to paste it into their own settings.
When this is useful
A few examples where this saves real time:
- You hired a new sales person and don't want to walk them through signature settings on day one.
- Legal wants a confidentiality disclaimer on every outgoing message from the firm.
- Marketing finally agreed on the new tagline and you'd rather not chase 30 people to update their signatures.
- You're running a white-label customer brand and need consistent contact details across the team.
Where to find it
Go to Domains, click the domain you want, then open the Signature tab. There are three settings: a mode, a position toggle for replies, and the editor itself.
Pick a mode
Three options, in increasing order of how strict you want to be:
- Off — the domain has no signature. Every mailbox owner sets their own from the webmail settings, the way they always have.
- Default for new mailboxes — when a brand-new mailbox is created on the domain, it starts with this signature already filled in. The owner can edit or delete it later. Existing mailboxes are left alone, so flipping this on won't surprise people who already have something they like.
- Enforced on all webmail send — the signature is appended to everything that leaves through the webmail compose window. Per-person signatures are ignored. This is the right choice for the legal-disclaimer case.
Position in replies
When someone hits Reply, the original message gets quoted underneath. You can pick whether the signature lands before the quoted text — which is what Gmail and Outlook do by default — or after it. The "after" option is mostly useful when you want a long legal footer to sit at the very bottom of the entire thread.
The editor
The editor handles formatted text, headings, lists, colors, links, tables, and images. Paste your existing signature HTML and it will render straight away — the toolbar buttons match what you'd find in any webmail composer.
Images need to be hosted somewhere reachable on the open web (an HTTPS URL). The editor doesn't accept uploads from your machine yet — that's coming in a future update.
What it does and doesn't cover today
Right now the signature is applied to mail that goes out through the TrekMail webmail. If someone on your team uses Outlook, Apple Mail, or Thunderbird via IMAP, their email client will keep using whatever signature is configured locally — TrekMail can't reach into a third-party app to override that. We're tracking the IMAP-client coverage as a separate piece of work; if you need it, let us know on a support ticket and that helps us prioritise.
Doing it from code
If you're automating this — say you're spinning up a domain per customer in a white-label setup — the same settings are available through the REST API and through the MCP tools your AI agent already has. See the API overview and connecting AI agents for the endpoint and tool names.